Tokyo  - US Defence Secretary Robert Gates on Wednesday told Japan's new government to quickly implement a 2006 agreement to relocate a US air base on Okinawa, or the United States would not withdraw Marines from the island to Guam, a news report said.

The relocation of the US Marine Corps' Futemma air base is the "linchpin" of a US troop realignment, Gates said in Tokyo after meeting with his Japanese counterpart, Toshimi Kitazawa, according to the Kyodo News agency.

"Without the Futemma facility, there will be no relocation to Guam, and without the relocation to Guam, there will be no consolidation of forces and the return of land in Okinawa," Gates said.

Under the 2006 agreement, which was reached with a previous Japanese government after years of negotiations, the Futemma air base, located in the centre of the city of Ginowan, would be moved to Okinawa's more sparsely populated coast.

But Prime Minister Yukio Hatoyama, who took office in September, has indicated that he wants the Futemma base moved to the main Japanese island of Honshu, or off Japan altogether.

Another key part of the 2006 agreement is the redeployment of 8,000 US Marines from Okinawa to the US Pacific territory of Guam.

Gates said it was time to implement the deal.

"Our view is this may not be a perfect alternative for anyone, but the best alternative for everyone," he said. "It is time we move on."

At the same time, however, Gates indicated he was prepared to make minor adjustments to the 2006 agreement. For instance, he said the base runway could be built offshore but said such a change was for the Okinawan and central governments to decide.

Hatoyama's government wants to end what it sees as Japan's dependence on the United States and is seeking more equality in relations with its ally.

On a local level, the US military presence has long caused tension with Okinawa residents, who have complained of crimes committed by US troops, aircraft noise and accidents.

Hatoyama's government also has baulked at extending the legal authorization for a Japanese mission in the Indian Ocean, in which it refuels US and other ships engaged in the Afghan conflict. That mission expires in January, and his administration favours putting its money into Afghanistan's reconstruction.

Gates, who was visiting Japan ahead of a planned trip there in mid-November by US President Barack Obama, called on Japan to provide financial aid for Afghanistan's military and police as an alternative to the refuelling mission.(dpa)