Russian President Vladimir Putin said Sunday that 755 U.S. diplomats will be expelled from Russia by Sept. 1, according to an interview on Russian television.
The expulsions had been announced Friday in response to a new law passed in Congress that expanded sanctions, but Sunday's statement was the first time a large number of Americans were confirmed as involved.
It was "a regrettable and uncalled for act," a State Department official told The Associated Press. Earlier, a State Department official told Fox News, "It is our policy to not comment on the number of individuals serving at our missions abroad."
Russia's Foreign Ministry said it is ordering the U.S. Embassy to reduce the number of embassy and consular employees in the country to 455.
"I decided it is time for us to show: We do not intend to leave U.S. actions unanswered," said Putin, according to Interfax News Agency.
The U.S. has taken an "unprovoked step towards worsening bilateral relations," Putin added.
He also said that Russia could consider other options in response to the U.S., but that he hoped it would not come down to that.
Putin noted the recent creation of a de-escalation zone in southern Syria as one example of how the countries have worked together.
However, in terms of general relations, Putin said: "We have waited long enough, hoping that the situation would perhaps change for the better. But it seems that even if the situation is changing, it's not for anytime soon."
The new American sanctions were in retaliation both for Russia's takeover of Crimea in 2014 and Russian interference in the U.S. 2016 presidential election.
The Associated Press contributed to this report.