"We can confirm that Russia expelled US Deputy Chief of Mission (DCM) to Russia Bart Gorman," a State Department spokesperson said.

"Russia's action against our DCM was unprovoked and we consider this an escalatory step and are considering our response," the spokesperson said.

"Now more than ever, it is critical that our countries have the necessary diplomatic personnel in place to facilitate communication between our governments," the official said.

Russia said Gorman was told to leave as a response to the US recently expelling one of Moscow's diplomats.

"The American diplomat was ordered to leave Russia in response to the unjustified expulsion of the minister-counsellor of our embassy in Washington," Moscow's foreign ministry spokesperson, Maria Zakharova, said on the Telegram messaging service.

It put the blame for regular reciprocal expulsions of diplomats on Washington.

"The mass expulsions of diplomats and the growing 'visa war' are not our choice," Zakharova said.

She alleged that Moscow "repeatedly and at different levels offered the American side to stop worsening the conditions for the functioning of diplomatic missions."

Russia has for months complained that American authorities have blocked visas to its diplomats, or issued them slowly.