Japan said on Tuesday (June 16, 2026) it has not yet decided whether its military will join efforts to help the resumption of shipping through the Strait of Hormuz after the U.S.-Iran peace deal.

U.S. President Donald Trump said the vital artery for oil and gas would be "completely open" from Friday (June 19, 2026) but added there was still "hunting" going on to ensure the waterway was de-mined.

Japan signed onto a joint statement issued on Monday (June 15, 2026) by European nations that they were ready for a "defensive and independent mission to reassure commercial shipping and conduct mine clearance operations" in the Strait. The statement added though that this would occur in accordance with "respective constitutional requirements".

Japan's constitution strictly limits the use of force to self-defence. Mr. Trump has pressed global allies including Japan to send warships to the region to help open the Strait. "At this point, no decision has been made regarding the dispatch of the Self-Defence Forces," Japanese Defence Minister Shinjiro Koizumi said on Tuesday (June 16, 2026), using the official name for Japan's armed forces. "We intend to consult closely with relevant countries, including our ally the United States, carefully assess the situation, and consider necessary measures within the framework of international and domestic law," Mr. Koizumi said.

In April, senior members of the ruling Liberal Democratic Party suggested that after fighting stops, Japan should consider deploying minesweepers and other vessels to clear any obstacles in the Strait of Hormuz, the Nikkei reported. Prime Minister Sanae Takaichi, currently at a Group of Seven summit in France, later reportedly said Japan will have various options after a ceasefire agreement.

“Japan's Maritime Self-Defence Force (MSDF) is considered adept at removing mines, with 16 vessels capable of such operations,” the Nikkei said. The Japanese military was involved in mine-clearance operations in 1991 after a ceasefire in the West Asia War.