This handout video grab released by the Russian Defence Ministry on February 9, 2022 shows combat crews of the S-400 air defense system driving during joint exercises of the armed forces of Russia and Belarus as part of an inspection of the Union State's Response Force, at a firing range in Brest region of Belarus. Image Credit: AFP

Washington: Russia expelled the number two US diplomat in Moscow on Thursday as tensions built over the threat to invade Ukraine, the US State Department said.

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