This story is breaking and will be updated as more information becomes available.

On Thursday, Russia inched closer towards the brink of war when a senior U.S. diplomat was expelled from Moscow.

The Hill reports:

Russia expelled a senior U.S. diplomat on Thursday, the State Department confirmed, the latest sign of tensions rising between Washington and Moscow as the Biden administration stepped up warnings of a possible Russian invasion of Ukraine.

A State Department spokesperson confirmed the expulsion of deputy chief of mission Bart Gorman, the No. 2 diplomat at the U.S. embassy in Moscow, and described it as “unprovoked.” Russia did not offer a reason for the decision to expel Gorman. The State Department said he had a valid visa and that his tour had not ended.

“We consider this an escalatory step and are considering our response,” the State Department spokesperson said.

“We call on Russia to end its baseless expulsions of U.S. diplomats and staff and to work productively to rebuild our missions,” the spokesperson said. “Now more than ever, it is critical that our countries have the necessary diplomatic personnel in place to facilitate communication between our governments.”