The transfer of thousands of US Marines from Japan to Guam may start as early as October 2024.
The speaker of the island's legislature told the Japan Times the tranfer plan involves about 1700 troops being permanently based on Guam and thousands more rotated every year.
The Marines are being moved from Okinawa after a deal was struck between the US and Japan to remove the unpopular military presence.
Many will be moved to Guam, a US territory, where a new military base is being built near the Air Force base at the top of the island.
The relocation is expected to cost more than $US8 billion.
But the plan is also controversial in Guam, where the Pentagon faces several legal challenges to the plan, including for live-fire ranges in the nearby Northern Marianas.