“The demands of the US authorities create a direct threat to the security of Russian citizens,” foreign ministry spokeswoman Maria Zakharova said.

“American special services intend on September 2 to carry out a search of the consulate in San Francisco including of the apartments of employees who live in the building and have immunity,” Zakharova added.

The US on Thursday ordered Russia to close its consulate in San Francisco as well as two annexes in Washington and New York, in a tit-for-tat response to Moscow’s forced reduction of US Diplomatic staff in their country.

The State Department stated that the decision was made “in the spirit of parity,” adding that the closures needed to be completed by tomorrow.

Zakharova said that the FBI had ordered diplomats to leave their accommodation for 10 to 12 hours with their families including young children and babies.

“We are talking about the invasion into a consulate and the accommodation of Diplomatic Staff, what’s more, they are being chucked out so that they don’t get in the way of the FBI agents,” Zakharova said.

“We express a resolute protest over Washington’s actions that ignore international law, and as is customary in diplomatic practice, we reserve the right to take retaliatory measures. That’s not our choice. They are forcing us into it,” Zakharova said.

Presidential aide Yury Ushakov described the latest US measures as “a kind of illegal takeover.” “We will think how to respond,” he added.

The latest US move came as a September 1 deadline was reached for Washington to comply with a Kremlin demand to slash staff numbers at its Russian diplomatic mission by 755 personnel.

The latest diplomatic spat is the latest twist in tortured ties between the US and Russia, which have slumped to their lowest point since the Cold War following the Kremlin’s seizure of Crimea from Ukraine in 2014.