WASHINGTON – U.S. Defense Secretary-in-waiting Mark Esper plans to visit Japan in early August, sources familiar with bilateral relations said Monday.

Esper, secretary of the Army, is expected to be confirmed Tuesday by the Senate. He is also considering traveling to South Korea and other countries, the sources said.

While in Japan, he plans to meet with Prime Minister Shinzo Abe and Defense Minister Takeshi Iwaya and push for a U.S. plan for a coalition of like-minded nations to safeguard shipping in the Middle East amid rising tensions with Iran.

U.S. President Donald Trump’s administration is asking allies to contribute personnel, naval vessels and funds for patrols in the Strait of Hormuz, the sea lane connecting the Persian Gulf and the Gulf of Oman through which more than a fifth of the world’s crude oil supply passes.

Esper may call for closer trilateral coordination with Japan and South Korea, at a time when ties between the two U.S. allies have chilled over wartime history and trade issues.

Esper became acting Pentagon chief in late June after Patrick Shanahan stepped down for family reasons. He was sworn in as secretary of the Army in November 2017.