President Bush announced agreement Friday on joint U.S.-Japanese development and production of an advanced version of the F-16 fighter jet, the FSX.

Following months of negotiations on a deal that at one point seemed in danger of being killed, Bush said the proposed arrangement would bolster the security of both nations without compromising U.S. technology."We did have have several initial concerns about the agreement. But I want to assure you that sensitive source codes for the aircraft's computer will be strictly controlled," Bush told reporters at the White House.

"Access will be granted to only those codes that are essential to complete the project," the president said.

Bush said, "In conclusion, the United States is the world's leader in aircraft manufacturing. I believe this aircraft will improve the defense of the United States and Japan. And this agreement also helps preserve our commitment that U.S. aerospace products of the future will continue to dominate the world market."

The proposed deal, which dates back to the final year of the Reagan administration, will now be sent to Congress for a 30-day review. Some members of Congress have expressed some strong criticism and reservations about the FSX deal.

Rep. Richard Gephardt, D-Mo., chairman of the House task force on the FSX, said the deal would "undermine our long-term competitiveness by giving the Japanese an edge in an area of U.S. dominance.

"If the Japanese are really serious about addressing our bilateral trade imbalance, common sense dictates that they buy our plane," Gephardt said in a statement. "I will lead an effort to ensure that this giveaway of American technology never sees the light of day."

The project had triggered an intense debate in the Bush administration.

The Pentagon took the lead in favor of the deal, saying it would increase the number of jets in strategic northeast Asia at no expense to the United States. Defense Department officials also argued that killing the deal would harm U.S. relations with Japan, one of the nation's leading trade partners.

But foes, led by Commerce Department officials, voiced concern that it would be a giveaway of U.S. technology and boost an eventual Japanese challenge to the United States in the aerospace field.

Bush's announcement followed a 45-minute meeting at the State Department between Japan's ambassador to the United States, Nobuo Matsunaga, and Secretary of State James Baker, Commerce Secretary Robert Mosbacher, Defense Secretary Richard Cheney, deputy National Security director Robert Gates and the new U.S. ambassador to Japan, Michael Armacost.

Under the proposed project, the United States would have a 40 percent work share in the initial development stage of the aircraft with a "similar" share when the aircraft goes into production.

Bush said, "We weighed this matter from the standpoint of trade, our industrial growth and technology transfer, as well as strategic and foreign policy considerations."

The president said, "I'm pleased to announce that the governments of the United States and Japan have reached understandings that will allow us to proceed with joint development of the FSX fighter aircraft."

Bush said, "This aircraft will improve the basic F-16 design and will contribute to the security of the United States and our major ally, Japan."

The FSX will have a new generation of engines and avionics systems. The Japanese government plans to build at least 130 of the planes in the deal, potentially worth $7 billion.

Negotiations broke down last month when the Japanese and the United States failed to agree on the exact proportion of the work to be guaranteed to U.S.-based companies. In the end, the United States, as it had sought, obtained at least 40 percent of the design and production contracts.

Bush refused to answer any questions after reading a brief statement in the White House press room. But afterward, administration officials - who spoke on the condition that they not be identified - gave a briefing to reporters.

They said the deal would be sent to Congress for review Monday. They said the agreement would proceed unless both the House and Senate overturned it within 30 days.

One official said that the administration economic and trade executives endorsed the accord.

"The economic agencies are fully satisfied," the official said, adding that Mosbacher - who initially led opposition to the deal - was happy with the agreement.

A Defense Department official stressed that the United States would not provide Japan with highly sophisticated, top-secret software used in the most advanced F-16 jets.