U.S. Defense Secretary Mark Esper has urged Japan to consider taking part in a coalition to protect shipping in the Strait of Hormuz.

Washington has been struggling to secure support for its efforts to counter Iranian activities in the sea lane, through which much of the world's oil passes.

"Any and every country that has an interest in freedom of navigation and freedom of commerce needs to really consider (being) involved in this type of monitoring of the strait," he told reporters Tuesday, while en route to Tokyo for talks with Japanese Prime Minister Shinzo Abe and Defense Minister Takeshi Iwaya.