TOKYO -- William Hagerty, the U.S. ambassador to Japan, will step down later this month as he prepares to run for Senate in the 2020 election.
The American Embassy in Tokyo made the announcement Tuesday. Joseph Young, the deputy chief of mission, will serve as the embassy's charge d'affaires in the interim.
U.S. President Donald Trump tweeted Friday that Hagerty would run for a Senate seat representing the state of Tennessee, adding that he has "my Complete & Total Endorsement!"
Hagerty, who was director of appointments for Trump's transition team, is believed to have a direct line of communication to the president. The Republican formerly ran an investment company and also served as commissioner of the Tennessee Department of Economic and Community Development.
As ambassador, he urged Japanese companies to boost investment and operations in the U.S. as part of Trump's push to narrow the countries' trade imbalance. Japanese foreign direct investment in the country grew by more than $50 billion during 2017, according to the U.S. Department of Commerce.
"Ambassador Hagerty is honored to have represented the President and the American people in his work to advance the U.S.-Japan Alliance, the cornerstone of peace and prosperity in the Pacific," the embassy statement said.
Speculation of a Hagerty bid for Senate had grown in Tennessee after the Republican incumbent said he would not seek reelection in 2020.
Young previously served as director for Japanese affairs at the U.S. State Department and as deputy foreign policy adviser for the U.S. Pacific Command.