Japan is considering sending the country's Self-Defense Forces to the Middle East for information-gathering and monitoring missions.
Government sources say the basic policy of such a dispatch was confirmed at a National Security Council meeting on Friday.
The operation would likely be centered on sending Maritime Self-Defense Force destroyers and patrol aircraft.
The United States is proposing an international coalition to help ensure safe navigation in the Strait of Hormuz in response to rising tensions over Iran.
But the dispatch would be separate from such a coalition, taking into account Japan's longstanding friendly ties with Iran.
The deployment would be part of the SDF's "survey and research" activities stipulated by law.
A senior Foreign Ministry official says the move would be aimed at ensuring the safety of Japanese vessels, and that the ministry will make its case to the US and Iran.