Japanese officials in Okinawa on Friday approved the long-stalled relocation of a controversial US military base, a breakthrough that could remove a running sore in relations between Tokyo and Washington.
The agreement will burnish the credentials of Prime Minister Shinzo Abe in the US, possibly taking some of the sting out of American criticism of his provocative visit Thursday to a war shrine seen by China and Korea as a symbol of Japanese militarism.
The issue has been deadlocked for years, with huge opposition to any new base among Okinawans fed up with playing host to an outsized share of the US military presence in Japan, and who want it moved off the island altogether.
Okinawa's governor Hirokazu Nakaima, long a thorn in the central government's side, this week met Abe, who pledged a big cash injection into the island's economy every year until 2021.
He emerged from the meeting declaring himself impressed with the package on offer, which includes a pledge to work towards the shuttering of Futenma within five years, and on Friday gave it his formal seal of approval.
"The imminent issue for us on Okinawa is to remove the dangerous airbase from the heart of the town as soon as possible," Nakaima told reporters.
"The prime minister is saying the government will work towards halting the Futenma operation within five years."
Abe praised Nakaima for making a "courageous decision", while Defence Minister Itsunori Onodera said the government "will do its utmost to relocate the base to Camp Schwab as quickly as possible".
But the news provoked anger in Okinawa, where thousands of protesters surrounded the local government office, media reports said, with footage showing demonstrators holding banners reading: "Never bend".
Several hundred had stormed the lobby of the building and were staging a sit-in protest, a government spokeswoman said.
The deal gives the go-ahead for landfill near Camp Schwab on the east of the island, one of a number of large tracts of land the US military uses. Two runways will be built atop the landfill.
Environmentalists say any development risks seriously damaging the coral reefs in the area as well as the delicate habitat of the dugong, a rare sea mammal.
Nakaima had been a bitter critic of the central government, which he says is unsympathetic to the southern tropical island and still treats it as an "unsinkable aircraft carrier" of the US military, more than 40 years after it was handed back to Japan.
But at Wednesday's meeting, the carrot of Abe's stimulus pledge — at least 300 billion yen ($2.9 billion) every year until fiscal 2021 — proved persuasive for the governor of Japan's poorest prefecture.
The US agreed to shut Futenma in 1996 partly in response to soaring anti-base feeling after the gang-rape the year before of a 12-year-old girl by three servicemen.
Its position in the middle of a built-up area also makes it less than ideal for the frequent flights by military aircraft.
However, resistance from local communities to any new site left the base in limbo, with Washington's hopes for a resolution regularly frustrated by weak government in Tokyo.
Relations between the two capitals dropped precipitously after the 2009 election of prime minister Yukio Hatoyama, partly on a promise that he would turf the base out of Okinawa, much to the irritation of Washington policymakers.
His subsequent flip-flop left Okinawans furious and feeling betrayed, and cast a further cloud over the issue.
The deal Abe appears to have struck marks a significant achievement, and one that is expected to smooth relations after years of frustration.
Observers have pointed to the timing and Abe's controversial visit Thursday to the Yasukuni war shrine, seen as a symbol in northeast Asia of 20th century Japan's brutal imperialism, and said his negotiating methods owed more to his fondness for splurging money.
"Abe flashed big cash around to get the nod from the governor, which saved him some face in Washington," said Tetsuro Kato, professor emeritus at Tokyo's Hitotsubashi University.