Moscow has repeated a threat to demand further cuts in the number of U.S. diplomatic personnel in Russia.
The head of the Foreign Ministry's North America department, Grigory Borisenko, delivered he warning in an interview published by the state-run news agency RIA Novosti on October 11.
Echoing remarks President Vladimir Putin made last month, Borisenko said that bringing the size of staff at the U.S. Embassy and consulates in line with that of Russia's diplomatic mission in the United States would mean reducing it "to 300 people or fewer."
In late July, Russia ordered the United States to cut the number of diplomatic personnel in Russia to 455 by September 1 -- a reduction of about two-thirds -- in retaliation for a new U.S. law strengthening sanctions imposed on Russia over issues including its aggression in Ukraine and alleged interference in the U.S. presidential election in 2016.
The United States responded by ordering Russia to vacate its consulate in San Francisco and trade annexes in Washington and New York, steps intended to produce parity in the sizes of the Russian and U.S. diplomatic missions.
But on September 5, Putin suggested that Russia could demand the United States reduce the number of diplomatic personnel by a further 155, down to 300. He said that would produce truer parity because, by his account, 155 of the 455 Russian diplomatic personnel in the United States work in connection with the United Nations.
Borisenko repeated that argument, saying that "in diplomacy, there exists an inviolable principle of reciprocity, and the Americans know his perfectly well."
Asked whether Russia might order the United States to close one of its consulates -- in St. Petersburg, Yekaterinburg, or Vladivostok -- Borisenko said Moscow "is not ruling out any scenario, including the establishment of real parity in the number of diplomatic personnel."
But he did not say when Russia might make a new demand.
"We'll see," he said, adding that Russia was considering a wide range of potential actions.
His comments came a week after the new U.S. ambassador to Russia, Jon Huntsman, took up his post in Moscow.
Receiving Huntsman’s credentials at a Kremlin ceremony on October 3, Putin voiced dissatisfaction with the state of bilateral relations and said that Russia wants “constructive, predictable, and mutually advantageous cooperation," but gave no indication whether Moscow plans to take steps in that direction.