Russian President Vladimir V. Putin announced on Sunday that 755 American diplomats would be expelled from Moscow by September 1.
The expulsions were ordered on Friday when Russia ordered the United States to reduce the number of their diplomats in the country as a mark of retaliation for new sanctions against Moscow passed last week by the U.S. Congress.
Putin, while speaking in a television interview on the Rossiya 1 network, said that "Russia's patience in waiting for improved relations with the United States had worn out."
"We waited for quite some time that maybe something will change for the better, had such hope that the situation will somehow change, but, judging by everything, if it changes, it will not be soon," Putin said, according to the Interfax news agency.
The Russian Foreign Ministry had earlier issued a statement saying the number of American diplomats in the U.S. Embassy in Moscow and its four consulates across the country should be reduced to 455 by September 1, which is the same as the number of Russian diplomats currently serving in the U.S.
It also said it would seize two U.S. diplomatic properties, including cottages just outside Moscow's city center and a warehouse facility in Moscow. The embassy properties must be handed over by August 1.
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Russia's move came a day after the U.S. Senate passed a bill expanding economic sanctions on Russia, as well as North Korea and Iran.
The massive vote margins reflected growing bipartisan anxiety over Trump's two meetings with Putin in Hamburg, Germany, this month.
Following the orders, Russian Deputy Foreign Minister Sergei Ryabkov threatened further retaliation against the U.S.
"If the U.S. side decides to move further towards further deterioration, we will answer, we will respond in kind," CNN reported Ryabkov, as saying to ABC's "This Week."
"We will mirror this. We will retaliate. ... But my whole point is, don't do this, it is to the detriment of the interests of the U.S."
The deputy foreign minister did not specify what Russia's plans for retaliation are, but said that the country has "a very rich toolbox at our disposal."
Earlier, Putin, speaking at a news conference in Finland, accused the U.S. lawmakers of "insolence."
"We are behaving in a very restrained and patient way, but at some moment we will need to respond," Putin told reporters.
"It's impossible to endlessly tolerate this kind of insolence toward our country. This practice is unacceptable. It destroys international relations and international law," he added.
The sanctions bill would slap new sanctions on Russia, and would set into law penalties former president Barack Obama's administration imposed on Moscow in December, for its meddling in the US election last year and for its aggression in Ukraine.
The bill also would give Congress veto power to block any easing of those sanctions.
The growing tensions between Russia and the U.S. over the sanctions bill come in the wake of the congressional investigations into Russian hacking into the 2016 election, which the U.S. intelligence services have said was an effort to influence the election in Trump's favour.