The transferral of 8,000 US marines to Guam is set to go ahead after Japan's Prime Minister announced he'd accept the plan for re-aligning troops on the island of Okinawa.
The shift to Guam, which is to occur by 2014 and expected to involve some 9,000 dependents, had recently been in doubt because the Japanese government wavered over the decision.
The plan had been part of a 2006 agreement between the previous government and the US, which the Prime Minister Yuko Hatoyama had pledged to break.
That agreement also provides for relocating some of the 49,000 military personnel on Okinawa to other parts on the island.
Mr Hatoyama has apologised for reneging on his pledge to the people of Okinawa, many of whom are deeply opposed to the military presence.