Updated with the U.S. State Department's response.
Moscow on Thursday said it was expelling two U.S. Embassy employees for allegedly "liaising" with a former U.S. consulate worker accused by Russian authorities of spying for Washington.
Russia's Foreign Ministry said the two American diplomats, Jeffery Sillin and David Bernstein, were engaged in "illegal activities by liaising with a Russian citizen, [Robert] Shonov."
"The U.S. ambassador was told that Sillin and Bernstein must leave the territory of Russia within seven days under the status of persona non grata," the Foreign Ministry said.
Shonov had worked for the U.S. consulate in Vladivostok for more than 25 years until 2021, when Moscow imposed restrictions on local staff working for foreign missions.
In May, he was arrested for gathering information on Russia’s "special military operation" in Ukraine, its military draft and protest activities in the run-up to the 2024 Russian presidential elections.
"The illegal activity of the U.S. diplomatic mission, including interference in the internal affairs of the host country, is unacceptable and will be resolutely suppressed," Russia's Foreign Ministry said.
Washington later denounced the expulsion of its two diplomats and promised to take countermeasures.
"This unprovoked expulsion of our diplomatic personnel is wholly without merit," State Department spokesman Matthew Miller told reporters.
"We regret that Russia has taken this path and you can certainly expect that we will respond appropriately to their actions."
AFP contributed to this reporting.