MOSCOW (AP) — The new U.S. ambassador to Russia has presented his diplomatic credentials to President Vladimir Putin at a ceremony in the Kremlin on Monday, a move that marks the formal start of Jon Huntsman's work in Russia.

Huntsman takes the high-profile job amid investigations into alleged meddling by Moscow in last year's U.S. presidential election.

Huntsman, a former Utah governor, has twice served as ambassador. He was the nation's top diplomat to Singapore under President George H.W. Bush and ambassador to China under President Barack Obama before returning to the U.S. to run for president in 2012.

The Senate last week approved Huntsman's nomination by voice vote.

The relationship between Russia and the U.S. has been marred recently by a series of expulsions of diplomats and closures of diplomatic missions.