The United States has retaliated against Russia by forcing the closure of its consulate in San Francisco and scaling back its diplomatic presence in Washington and New York.
The move is in response to the Kremlin forcing a cut in US diplomatic staff in Moscow, the State Department said.
Spokesman Heather Nauert said the move brings the US and Russia into "parity", with each having three consulates in the other country.
Moscow forced the cut in American diplomatic staff earlier this year in retaliation for US sanctions.
Washington had to reduce its diplomatic staff by 755 people.
Secretary of state Rex Tillerson had said the US would respond by September.
The Russian offices must close by Saturday.
The order affects Russia's "chancery annex" in Washington and a "consular annex" in New York.