Nearly 100,000 people rallied on Japan's Okinawa on Sunday to demand a U.S. airbase be moved off the island, media said, deepening the prime minister's woes as he struggles to resolve a feud by an end of May deadline.
Voters' perception that Prime Minister Yukio Hatoyama has mishandled the row over the U.S. Marines' Futenma airbase on Okinawa, a reluctant host to the bulk of U.S. forces in Japan, is eroding support for his government as a key mid-year upper house election approaches.
Hatoyama's Democratic Party, which swept to power in a general election last year, needs a decisive victory in the upper house poll, expected in July, to enact legislation smoothly.
Some, even within Hatoyama's own party, say failure to resolve the row by his self-imposed deadline could force him to resign before the election.
Crowds of residents, many wearing yellow as a symbol of protest, gathered in the town of Yomitan on Okinawa one day after a U.S. newspaper said Tokyo was moving towards broadly accepting a 2006 deal to relocate Futenma's functions from the center of a city to a less populous part of the southern island.
About 90,000 people, including representatives of all major parties, took part in the rally, Kyodo news agency said.
"To save the life, property and living environment of citizens, we Okinawans urge both Japanese and U.S. governments to give up the relocation of the Futenma airfield within the prefecture," Kyodo quoted a resolution adopted at the rally as saying.
U.S. Assistant Secretary of State Kurt Campbell is scheduled to visit Japan in the next few days.
Hatoyama, who has said any new plan must win local understanding as well as satisfy the United States, on Saturday repeated his objection to the original 2006 plan.
In the campaign that swept his Democratic Party to power last year, Hatoyama had raised hopes the airbase would be moved off Okinawa, if not outside Japan entirely.
The Washington Post said on its website that Japanese Foreign Minister Katsuya Okada told U.S. Ambassador John Roos on Friday Tokyo was moving towards accepting major parts of the 2006 deal.
It said Okada had suggested some changes to the 2006 deal, including altering the design of the runway at the new air station and moving parts of the facility to an island about 100 miles from Okinawa.
It was unclear whether the proposal referred to the small island of Tokunoshima, where a crowd of 15,000 protested against accepting the airbase last week.
The row has not only ruffled ties with Washington but dented the government's ratings with voters.
Support for Hatoyama's government has fallen to around 30 percent, after previous highs above 70 percent, on growing voter doubts over his decision-making skills, clouding his Democratic Party's chances of a decisive win in the upper house vote.