U.S. Democratic and Republican senators urged President Joe Biden on Tuesday to expel Russian diplomats if Moscow did not issue more visas for Americans to represent Washington in Russia.

“Those proposing such steps are apparently pushing for the closure of U.S. foreign institutions in Russia,” Russia’s foreign ministry said, the Interfax news agency reported.

“They must understand that the blame for this will lie with them,” the ministry said late on Tuesday.

It said that Moscow did not have that number of diplomats in Washington and that the proposal appeared to include diplomatic staff at Russia’s mission at the United Nations.

The U.S. proposal by the leaders of the Senate foreign relations and intelligence committees would mark an escalation in long-running tensions between Moscow and Washington over the number of diplomats they have in one another’s countries.

Russia in August banned the U.S. embassy in Moscow from retaining, hiring or contracting Russian or third-country staff, except for guards, forcing the mission to let go 182 employees and dozens of contractors, the State Department said.

(Reporting by Tom Balmforth; editing by Andrew Osborn)