Defense Secretary Lloyd Austin spoke with his Russian counterpart on Friday, the first contact between the two since Moscow began its invasion of neighboring Ukraine in late February.
Pentagon spokesman John Kirby said Austin urged an immediate halt to operations in Ukraine during an hour-long discussion with Russian Defense Minister Sergei Shoigu.
A senior Ministry of Defence official said Mr Auston sought an opportunity to speak with Mr Shoigu.
“He thought it was important to make the call,” a Defense Department official told reporters.
“Our inability to establish communication is not for lack of trying.”
Pentagon officials declined to release information on discussions between Washington and top military leaders in Moscow.
“The secretary of state did express an interest in keeping the lines of communication open,” the senior defense official said. “We received information about keeping the lines clear.”