A Russian plane landed at Washington's international airport on Saturday to pick up a dozen diplomats from Moscow's UN mission who were expelled by Washington.

Iran PressEurope: Tensions have flared between Washington and Moscow since Russia launched a military operation against Ukraine a week ago.

The plane, an Ilyushin Il-96, left Moscow en route to St. Petersburg on Friday night and arrived at Dulles airport outside Washington at 2:10 p.m. eastern time on Saturday. It is unclear what time it will depart back to Russia.

Russian diplomats were expelled this week from their posts at the United Nations over U.S. national security concerns, officials said.

Russia denies the allegations and says it will retaliate for their expulsion. A Rossiya Special Flight Squadron is flying to Washington from St. Petersburg to bring the diplomats to Russia, foreign ministry spokesperson Maria Zakharova said.

"This plane will bring back home the Russian diplomats whom the Government of the United States has declared personae non grata," Zakharova said.

The same plane appears to have been used to fly Russian officials from Moscow to Belarus for the first two rounds of peace negotiations with Ukraine. 219