The United States has expelled two Russian officials following an attack on an American diplomat outside the US Embassy in Moscow last month, the State Department says.
The US diplomat was attacked by a Russian guard on June 6 and the incident was caught on a security camera.
Although the Russian Foreign Ministry asserts the American was a CIA agent who refused to show his identification documents and punched the guard in the face, the US State Department says the attack was "unprovoked and it endangered the safety of our employee."
"Instead of the CIA employee, who was in disguise, as we understand, it could have been anyone — a terrorist, an extremist, a suicide bomber," Russian Foreign Ministry spokeswoman Maria Zakharova told state-owned NTV television this week.
However, US State Department spokesman John Kirby told reporters on Friday that “the Russian claim that the policeman was protecting the embassy from an unidentified individual is simply untrue."
"On June 17, we expelled two Russian officials from the United States to respond to this attack," Kirby added.
The Russian security services had "intensified their harassment against US personnel in an effort to disrupt our diplomatic and consular operations," he said, noting Washington had privately "urged" Moscow to stop such behavior.
The footage shows that a man gets off a yellow taxi that pulls up in front of the entrance into the US embassy compound.
He then walks towards the entrance, but a guard darts out of a police sentry box in front of the entrance. The officer grabs the man and throws him to the floor about two meters from the entrance of the embassy building.
The man manages to wriggle his way towards the door and opens it, while the Russian officer is still lying on top of him, pinning him to the floor.
The incident has aggravated the already strained relations between the US and Russia which find themselves on opposite sides of conflicts from Ukraine to Syria.