Novak Djokovic’s family have said he is the victim of “a political agenda” aimed at “stomping on Serbia” as protesters in Belgrade called for his release and Serbia’s president insisted “the whole country” was behind him.

The 34-year-old world tennis No 1, who was born in the Serb capital, is in detention in an immigration hotel in Melbourne pending a legal challenge to Australia’s decision on Wednesday to cancel a visa that would allow him to play in the Australian Open.

Demonstrators gathered outside the Serb assembly on Thursday afternoon after a call for support from Djokovic’s family. The player’s father told a press conference that he could not be defeated “by anyone, not even the Australian government”.

Djokovic was being “persecuted”, Sjrdan Djokovic said. “They’re keeping him in captivity. They’re stomping all over him to stomp all over Serbia and the Serbian people. [Scott] Morrison [Australia’s prime minister] and his like have dared attack Novak to bring Serbia to its knees.”

Australian officials have said the player, who has refused to reveal his Covid vaccination status but previously said he was opposed to vaccination, was refused entry because he failed to meet vaccination exemption requirements.

Read the full report from Jon Henley and Milivoje Pantovic here: Djokovic father says visa row aimed at ‘stomping on Serbia’

Related: Djokovic father says visa row aimed at ‘stomping on Serbia’

The Stormont assembly is set to be recalled early from its Christmas recess to discuss the Omicron surge in Northern Ireland, PA reports.

It follows a recall motion submitted by Sinn Féin MLA Pat Sheehan, which was backed by SDLP and Alliance party members.

On Thursday, the speaker, Alex Maskey, confirmed that a sitting of the assembly’s plenary would take place at noon on Monday.

MLAs would debate a motion around the opening of schools amid the recent record-breaking wave of Covid Cases.

The motion expresses “serious concern at the lack of planning” by the education minister, Michelle McIlveen.

It calls for the minister to “urgently develop a plan that puts the safety of pupils and staff first, through the installation of air-monitoring and air-filtration devices in all classrooms”.

It also calls for staffing shortages to be addressed by “utilising and deploying additional teaching capacity to keep schools open and safe”.

Teachers’ unions have warned that the return of children to the classroom will lead to a further increase in transmission and that members had concerns about contact tracing as well as staffing levels.

Earlier this week, McIlveen said her priority was to keep children in school and added that her department continued to liaise with the Department of Health as well as schools over Covid concerns.

Sheehan welcomed the plenary sitting and urged McIlveen to address MLAs. He said:

I welcome confirmation that the assembly will be recalled to discuss the need for schools to reopen safely and the extra pressure faced by school staff as a result of rising Covid-19 infection rates.

The education minister needs to come to the assembly on Monday and set out a return-to-school plan which puts the safety of pupils, teachers and parents first.

Here is my colleague Peter Walker’s story on Boris Johnson criticising anti-vaccine activists for spreading “nonsense” on social media, while stressing that he does not support moves to overtly pressure people into having Covid vaccines.

Related: Johnson condemns anti-vax ‘nonsense’ but jabs will stay voluntary

Austria’s government has said it was making medical grade masks compulsory outside to ward off a new lockdown as Omicron cases rise, AFP reports.

Chancellor Karl Nehammer revealed the decision on Thursday, telling reporters the situation was “very serious” with Omicron’s degree of contagion posing “a new challenge”.

Austrian reported 8,853 new Covid-19 cases on Thursday, nearly three times above the daily average number of infections last week.

Medical grade FFP2 face coverings had already been compulsory on Austrian public transport and in enclosed spaces since last January.

FFP2 masks offer better filtration than their surgical equivalent and cover the face more effectively.

Austria is also tightening its health pass controls but loosening restrictions including on self-isolation of those who test positive and those with whom they have been in contact to avoid economic paralysis. [see 3.25pm.].

Nehammer said Vienna was not ruling out a new lockdown should hospitalisations surge, the most recent one having ended on 12 December for those vaccinated.

Those yet to be jabbed must stay at home except for reasons including work and buying food in a country where about one third of residents have not been jabbed – one of the highest rates in western Europe.

Here is the moment the UK prime minister described anti-vaxxers’ social media messages as “mumbo jumbo”.

Boris Johnson said he wanted to keep coronavirus vaccination voluntary in the UK unlike other European countries that have begun introducing mandatory vaccination.

Dozens of protestors have gathered outside the Serbian parliament in central Belgrade to show their support for Novak Djokovic, the BBC reports.

It came after the tennis star’s father urged his fans to respond to Australia’s decision to refuse the world number one entry to the country. The chain of events has put Djokovic at the centre of a diplomatic and political furore over the validity or not of his medical exemption from vaccination rules.

Shortly after arriving in Melbourne for the Australian Open, Djokovic was taken to a government detention hotel in the city, where he is being held pending a court appeal. The Australian Border Force said he had failed to provide enough evidence that he was medically exempt from coronavirus rules that all players in the Australian Open must be double-jabbed.

His father Srdjan said the player was being made to suffer “terrible” hotel conditions. Several anti-vaccination protesters, many of them holding Serbia flags, have also turned up outside Djokovic’s hotel in Melbourne to rally against the treatment of the tennis star.

But tennis player Rafael Nadal has shown much less sympathy over the visa debate, reports Guardian sports writer Tumaini Carayol from Melbourne:

Speaking after he successfully returned to competition for the first time since August with a straight sets win over Ricardas Berankis of Lithuania, Nadal reiterated that the clearest way to ensure participation in Melbourne was through embracing vaccination and that Djokovic had known the conditions for many months.

First up, a little light relief to brighten your day. To encourage people to get their Covid-19 jabs, a campaigner in Germany has filmed a flock of sheep forming the shape of a syringe from the air, reports Reuters. Here is some marvellous footage of the wooly creatures’ performance.

“Sheep are popular with people and carry positive emotional connotations. So perhaps they can reach many people emotionally when logic and scientific reasoning don’t do the job,” the organiser of the campaign, Hanspeter Etzold, told Reuters.

“I have noticed how enthusiastically the sheep are received and that it simply reaches people deep inside, which is perhaps not possible rationally, with rational arguments,” he said.

The sheep, which belong to the shepherd Steffen Schmidt and his wife, followed pieces of bread laid on the ground to create the 100-metre-long syringe shape as they were filmed from the air.

Good afternoon. I’m Georgina Quach, taking over from Lucy Campbell while she takes a lunch break. I’ll be updating the blog with more global coronavirus news as it develops. Please feel free to contact me if you have a story or tips to share. You can reach me on:

Email: [email protected]

Twitter: @georginaquach

Hospitals outside London could end up treating even more Covid patients than at the peak of the pandemic last January, a senior NHS leader has said.

Soaring infection rates in the north of England mean that one NHS trust expects to have 30% more Covid cases next week than it had at the last peak, the chief executive of NHS Providers said.

Chris Hopson said he fears that hospitals outside the capital will not be as able to cope with the new wave of admissions as those in London. This was because they had deeper staffing problems, higher levels of sickness absence, older populations and in some cases worse social care provision, he said. NHS Providers represents all the 213 NHS trusts in England.

Drawing a contrast between the ability of trusts in London and the rest of England to withstand the intense pressures of Omicron, Hopson said in a series of tweets that in the bulk of the country, “overall Covid cases v previous peaks could be much higher”.

He added: “London currently [circa] 50% of Jan 2021 peak Covid hospital load. One northern trust already at 70% of Jan 2021 peak and predicting [circa] 130% next week.”

Some trusts outside London had as many as 19% of their staff absent because of Covid, much higher than the 10% off sick or isolating that other NHS organisations had been reporting, he added.

Hopson said he had spoken to chief executives of more than a dozen trusts outside London over the previous 24 hours.

They all, unanimously, challenged the assumption that the rest of the country will automatically follow London on the shape and scale of, and ability to ‘cope’ with, pressure.

CEOs outside London gave a number of reasons why their local system may be less able to cope with pressures than London has done. Demographics, patterns of infection, hospitalisation and sickness absence will be different.

So we are likely to see a very varied pattern emerging over next days and weeks, with some trusts finding it easier to ‘cope’ than others. With London trusts at ‘more able to cope’ end? Hence why some trusts now declaring critical incidents – around two dozen now.

More on this story here: Hospitals outside London ‘expect more Covid patients than last January’

Related: Hospitals outside London ‘expect more Covid patients than last January’

Portugal has said it will allow students to return to school from next week and nightclubs to reopen on 14 January despite a record surge in Covid cases, with hospital admissions still well below levels seen earlier in the pandemic, Reuters reports.

“It is evident that the Omicron variant is less severe … vaccination has been effective against [it],” the prime minister, António Costa, told a news conference on Thursday, referring to the fast-spreading variant that emerged in late 2021.

“That’s why we have a much lower number of hospitalisations, fewer people in ICU and deaths,” he added.

The variant hit Portugal – one of the world’s most vaccinated nations, with 89% of its people fully inoculated – in November, leading to an increase in cases. These reached a record on Wednesday of close to 40,000 new infections.

Authorities registered 14 fatalities on Wednesday, far lower than the more than 300 daily deaths in the previous peak of the pandemic in late January, when the vaccination campaign had just kicked off.

Hospitals had 1,251 patients with Covid compared with a peak of 6,869 on 1 February.

From Monday, only coronavirus-infected people and those who live with them need to isolate, while those who have received a booster shot – a total of about 3 million people – no longer need to do so.

Students can return to school on Monday but a work-from-home order, imposed around Christmas, will stay in place until 14 January, Costa said.

Nightclubs and bars can reopen on 14 January, but a negative test will be required to enter. A negative test will also continue to be requested from all air passengers travelling to Portugal.

The surge in cases comes three weeks before a snap general election on 30 January, and Costa said authorities would do everything in their power to ensure all people, including those in isolation, can cast their ballots.

The president, Marcelo Rebelo de Sousa, said on Wednesday isolation could be temporarily suspended on election day.

A Hong Kong cabinet minister was sent to a quarantine camp on Thursday after he was deemed a close contact of a preliminary coronavirus case at a large party attended by other government officials and lawmakers, AFP reports.

The home affairs minister Caspar Tsui was among more than 100 guests at a birthday celebration on Monday evening that was also attended by city police chief Raymond Siu and head of immigration Au Ka-wang.

Tsui was classified as a close contact because he was there after 9.30pm, when a person suspected to have been carrying the virus attended.

Siu had left beforehand and officials said they were still trying to work out when Au left.

City leader Carrie Lam told reporters she was “very disappointed” senior officials attended the party just three days after health officials had advised the public to avoid large gatherings.

“My colleagues apparently have not taken the advice of the secretary for food and health, so how could they set a good example for the people of Hong Kong?” Lam asked.

Tsui issued an apology on Facebook.

Like China, Hong Kong has maintained some of the world’s strictest quarantine measures and travel curbs, which have kept the city mostly coronavirus-free but internationally isolated for some 22 months.

A small local outbreak of the Omicron variant which began with airline crew from Cathay Pacific has been detected in recent days sparking warnings, new social distancing measures and flight bans on eight countries.

At the time of Monday night’s party, banquets of up to 240 were still permitted but Lam said government officials should have “led by example” and heeded calls to avoid such gatherings.

She said an investigation by her office discovered 10 government officials attended the party – eight of whom could prove they had left before 9.30pm and therefore did not need to be sent to quarantine.

Local media reported three city legislators also attended the party, held for a member of China’s top lawmaking body.

Lam did not comment on those reports but confirmed the city’s legislature and main government offices were being disinfected.

Twenty lawmakers met Xia Baolong, Beijing’s Hong Kong and Macau affairs chief in Shenzhen, on Wednesday but it was unclear if the three who attended the party were among that group.

A day earlier Lam had lambasted the leadership of Cathay Pacific, saying they should take responsibility for attendants who had breached home-quarantine rules.

She said society was “paying a huge price” for the Omicron outbreak and even hinted that the city might look at legal options against the carrier.

Last year immigration head Au was among three government officials who were fined after they broke social distancing rules to eat at a luxury clubhouse.

Ukraine is offering booster vaccines to all adults as the Omicron variant spreads and is likely to lead to a surge in infections next month, the health minister Viktor Lyashko has said.

After several periods of strict restrictions, the average daily number of coronavirus cases in Ukraine fell in early January to about 4,000 from above 10,000 in early December.

“The medical system is preparing for another increase in the number of Covid-19 cases in Ukraine,” Lyashko said in a post on Facebook on Thursday.

“We call on all Ukrainians to make a conscious choice in favour of vaccination against coronavirus disease and help us overcome the epidemic,” he said.

He added that all vaccinated citizens aged over 18 will be eligible for a booster shot of either the Pfizer or Moderna vaccines.

In the country of 41 million people, only 13.9 million have received two doses. The country has officially recorded 97,000 deaths from Covid since the pandemic began.

Data from Israel on Thursday supports growing evidence worldwide that Omicron causes milder illness than previous coronavirus, even as the country grapples with a record number of daily infections, Reuters reports.

Total hospitalisations on Wednesday stood at 363 patients, after the health ministry reported more than 16,000 new cases – a record high in Israel since the start of the pandemic – with a daily increase of 34 people falling severely ill.

During the height of Israel’s Delta variant wave, the record number of people infected topped 11,000, with the number of those being severely ill increasing daily by around 100, and 1,300 people hospitalised.

“Our initial data, which is not yet entirely accurate, points to seven to eight people hospitalised for 1,000 infected, two of whom will fall severely ill or worse,” Sharon Alroy-Preis, the ministry’s head of public health, told Army Radio.

“This is a significant change from Delta which saw far more – at least 10 severely ill for every 1,000 infections,” she said.

A World Health Organization official said on Tuesday that more evidence was emerging of Omicron affecting the upper respiratory tract, causing milder symptoms than previous variants and resulting in a “decoupling” in some places between soaring case numbers and low death rates.

With infections rising fast, Israel’s testing centres have come under intense pressure, prompting health officials to prioritise risk groups and to trust younger, vaccinated populations to test at home if exposed to a carrier.

Risk groups have also been given the green light for a fourth dose of a Covid vaccine and for Pfizer’s and Merck’s antiviral Covid medications.

A week into a fourth dose trial at a major Israeli hospital, researchers saw participants’ antibody levels increase five-fold.

But Gili Regev-Yochay, who is leading Sheba medical centre’s study, said that while the jump restored protection provided by a third dose, it was lower than what she had hoped for.

“I expect to see it continue rising, the peak of antibodies usually occurs two to four weeks in,” she told Army Radio.

Malaysia has granted conditional approval for the use of Pfizer’s Covid vaccine for children aged between five and 11, the health ministry said on Thursday.

The country’s drugs regulator has also cleared a vaccine made by Chinese firm CanSino Biologics to be used as a booster shot for adults over the age of 18, health minister Khairy Jamaluddin said in a statement.

Malaysia, which has one of the highest vaccination rates in south-east Asia, last week cut waiting times to encourage more people to take a booster jab, in a bid to stem the spread of the highly infectious Omicron variant.

Most of the country’s population has received two doses of the vaccine, including nearly 98% of adults and 88% of those aged between 12 and 17, government statistics show.

Malaysia has reported 245 Omicron cases, the majority of which were Muslim pilgrims returning from Saudi Arab