This is the stunning new riverside Embassy building constructed by the US government at a cost of £750 million (1 billion dollars)
It has taken four years to complete the building, which will have some 800 staff located along 12 storeys
Woody Johnson, the US Ambassador to Britain, has shown off his new £750 million embassy building in south London.
The structure is reckoned to be the most Expensive Embassy building in the world and features state-of-the-art security systems.
The new building is expected to be officially inaugurated in February during President Donald Trump's planned working visit to the UK.
Ambassador Woody Johnson said the new £750m building was a 'signal to the world' that the special relationship is as strong as ever.
He said he would like to have President Trump at the Embassy's official opening in February.
He said: 'President Trump wants to work more closely than ever with the UK, and it will make both of our countries more prosperous and secure.
'So the new embassy is a signal to the world that this special relationship that we have is stronger and is going to grow and get better.
The new building is designed to make the most of of space and natural light to encourage 'transparency and openness'
'He mentioned that to me himself ... He said "I want you to make it stronger", and I intend to do that if I can.'
The new building features 518,000 square feet of space - far more than the 225,000 square feet in Grovesnor Square. However, three of the nine floors at the old building are below ground to confirm with stringent height restrictions in Mayfair.
Acclaimed US architect firm Kieran Timberlake was selected to design the new, carbon-neutral embassy south of the river.
In environmental terms, it will be nearly self-sufficient in energy production and even capable of operating off-grid 'for an extended period', according to officials.
Unlike most glass office buildings, which appear slick and hard-edged, this one will look soft and pillowy thanks to the lightweight plastic scrims that will be attached to the facade like boat sails.
The scrims will do triple duty. They are made from the same 'Etfe' fabric that was quilted on to the Beijing Watercube for the Olympics, they will be embedded with photovoltaic cells that can convert sunlight into energy, even in soggy London.
They will also act as sunscreens to keep interiors from overheating. And because the fins are pinched at regular intervals, they create a rippling, sculptural effect on the glass surface.
Ambassador Johnson open the Embassy today for a special tour in advance of his staff moving in next month