U.S. President Donald Trump on Tuesday nominated former Governor of Utah Jon Huntsman as new U.S. ambassador to Russia.

Huntsman, a Republican who served as ambassador to Singapore in early 1990s and to China from 2009 to 2011, currently serves as chairman of both the Atlantic Council, a U.S. think tank, and the Huntsman Cancer Foundation.

If confirmed by the U.S. Senate, Huntsman would take on the diplomatic post of increasing importance to a country whose relationship with the United States has sunk to new lows in recent years after the Ukraine crisis and alleged Russian meddling in the U.S. election.

The nomination also came at a time when the U.S. Justice Department appointed former FBI Director Robert Mueller as special counsel to oversee the probe into ties between Trump campaign and Russian officials.