Over the angry objections of demonstrators, the governor of Okinawa today announced his support for a plan to relocate a U.S. air base on the island, a key step in resolving a long-festering issue between the United States and Japan.

But the move seems likely to reignite the storm in Okinawa over the World War II legacy of the U.S. presence here. Bowing to the resentment of Okinawans over the numerous American bases on the small island, Gov. Keiichi Inamine added a potential deal breaker to his support for relocating the Futenma Marine Corps Air Station to a more sparsely populated area 25 miles north in Nago.

Inamine said the new air base should revert to civilian control in 15 years, a requirement the U.S. government flatly rejects. Tokyo must now find a way to finesse the governor's deadline, or watch the loss of its second attempt in four years to resolve the dispute.

"Everybody knows the U.S. position. Everybody knows the [Japanese] central government position. But for the benefit of the people of Okinawa, the deadline is hard to back down from," said Inamine's deputy, Reiji Fumoto.

The U.S. military said the move would not compromise its military preparedness in Asia. "We have always said that moving Futenma is a major step to reducing our footprint on the island, and we welcome it," said Marine Capt. Joseph Plenzler, a spokesman at the air base. "We will accept any alternative Okinawa wants, as long as it meets our requirements."

Futenma is among the smaller of the dozen U.S. bases on Okinawa. But it has become the sharpest thorn in relations involving the United States, Japan and Okinawa, Japan's southernmost and perhaps most independent-minded state.

After the 1995 rape of a 12-year-old schoolgirl by three American soldiers outraged Okinawans, the U.S. government offered to move Futenma, which has long irritated residents because of the noise and its location in the heart of the city of Ginowan.

In 1997, the proposal to move the base to a floating heliport near Nago was defeated by rising sentiment--encouraged by the former Okinawa governor--that the base should leave the island completely. Inamine, elected last year on a more moderate platform, said today he had made an "agonizing decision" to revive the plan and relocate the base along the shore of Camp Schwab near Nago.

But even as he spoke, shouting demonstrators tried to get into the news conference. The governor fled briefly to a phalanx of security men when it appeared that the demonstrators might burst into the room.

"They did this in secret because they are afraid of us," said Shinichi Isa, referring to the governor's announcement, originally planned for Wednesday. He spoke to about 150 demonstrators outside the government building, who chanted "Governor, listen to the people," and "Protect the environment."

Inamine has sidestepped the question of whether the airstrip should be built on the water, which would anger environmentalists, or on the land, which would bring opposition from nearby fishermen. Opponents promptly announced a petition drive to defeat the relocation. They have threatened a similar petition effort to recall the mayor of Nago if, as expected, he supports the plan.

"The U.S. forces took the land, without any consideration to the local people, and have kept the bases there," complained Masaru Shinsatu, as he stood near a banner at the rally. "In the last 54 years, the Okinawa people have asserted they wanted all the bases withdrawn from the island."

U.S. bases occupy nearly a fifth of Okinawa's land, planted there after the fierce fighting in World War II. Okinawa was the only land battleground in Japan, and the island prefecture, or state, was not returned to Japan's sovereignty until 1972. About two-thirds of the more than 50,000 U.S. troops stationed in Japan are on Okinawa, which includes the largest Marine contingent outside the United States.

The Japanese central government has supported the U.S. troop presence here and has been frustrated at local opposition to resolving the Futenma issue. President Clinton has said he wanted the issue resolved before he attends the summit meeting of the world's top industrialized nations next July in Okinawa.

Okinawans have been ambivalent about the bases. They resent the U.S. military presence and the bases, but they also recognize the economic benefit the bases bring an island with lagging economic prospects.

"Okinawans are fed up with seeing the fences of the bases," said Yoshitaka Toyohira, the political editor for the local Okinawa Times. "We have seen that since we were a child, and the next generation should be able to live without it."

But the central government is promising to accompany the base relocation with a $95 million package to help Okinawa's economy.

Futenma's 1,188 acres, built in 1945 as a B-29 landing strip, house 71 aircraft, most of them helicopters. U.S. officials said they could relocate the helicopters with an airstrip much shorter than Futenma's 9,000-foot runway. About 3,700 Marine personnel are based there.

Special correspondent Shigehiko Togo contributed to this report