By Chris Hogg
BBC News, Tokyo
The US and Japan have begun two days of talks in Tokyo aimed at breaking the deadlock over how to reorganise tens of thousands of American troops.
Japan's citizens complain about military-related noise and crime
The talks were supposed to have been concluded at the end of last month.
But there are still disagreements over how to achieve the reductions in troops numbers and redeployments that have been promised.
Six months ago the two sides agreed the broad outline of a plan to move some of the 50,000 US troops stationed here.
Some would leave the country, others would be moved around to different bases within Japan.
The plan is part of the US military's realignment of its forces worldwide. It is also designed to lighten the burden on the southern Japanese island of Okinawa, which hosts the majority of the US troops.
In recent months though, the plan has run into trouble as the two sides argue over who should foot the bill.
The United States wants Japan to pay three quarters of the $10bn it will cost to move 7,000 US marines from Okinawa to the US territory of Guam. Japan has offered to pay just a third of the cost.
Recent opinion polls here suggest most Japanese support their government's position.
There have been disagreements, too, over plans to move an airfield which is currently in a densely crowded urban area in Okinawa.
The Japanese government has found it hard to persuade other communities to accept a move of the airfield to their area.
Last week though, the city of Nago in central Okinawa agreed to host it.
Publicly both sides are upbeat now about the chances of an agreement. But before these two days of talks are concluded there's a lot of horse trading still to do.