U.S. Ambassador to Japan William Hagerty will leave the post "later this month," the U.S. Embassy in Tokyo said Tuesday.

The U.S. top envoy "is in the process of resigning" as ambassador, the embassy said in a statement.

U.S. President Donald Trump wrote in a tweet last week that Hagerty will run for the Senate in 2020.

The embassy said in a statement that Joseph M. Young, deputy chief of mission, will be taking on the position of acting ambassador.

Hagerty became a U.S. Ambassador to Japan in July 2017.