Lawmakers angered by China's detention of U.S. military personnel are pressing the Bush administration to sell Taiwan the most sophisticated defensive weapons it wants. President Bush is expected to decide by the end of the month.

"The people who were on the fence with respect to arms sales to Taiwan are showing movement in our direction," Rep. Tom Lantos, D-Calif., said Thursday. "Congressional sentiment has shifted, and American public opinion has shifted."

Lantos, top Democrat on the House International Relations Committee, supports fully granting Taiwan's weapons wish list.

At the same time, there are fears on Taiwan that Bush may be so eager to soothe U.S-China tensions in the aftermath of the April 1 collision of a U.S. spy plane and a Chinese jet fighter that he will shy away from selling the most advanced weapons.

The Navy plane's 24-member crew returned to the United states on Thursday after 11 days of tense negotiations between Washington and Beijing. The aircraft remained in Chinese hands.

Taiwan's top policy-maker on China, Tsai Ing-wen, said that as the United States and China resolve such sticky issues as returning the damaged spy plane and the future of U.S. reconnaissance flights, the danger heightens that Taiwan's interests will be ignored, especially about weapons.

"We have to be very careful in observing the developments of the case," Tsai said Thursday at a luncheon with the American Chamber of Commerce in Taipei.

Bush is to decide by the end of this month whether to let Taiwan buy its requested arsenal of high-tech military hardware, which includes four destroyers armed with the Navy's most-advanced Aegis anti-missile combat radar system, to deploy against a missile buildup on the mainland across the Taiwan Strait from the island.

Beijing fears the destroyers would give Taiwan a military advantage, and the Aegis destroyers could be incorporated into a U.S. anti-missile system. The Bush administration wants such a system but has not decided the form it would take.

China's communist-led government considers capitalist Taiwan a rebellious province. It maintains the right to restore the island to the country by force if necessary.

Sen. John Kerry, D-Mass., said the United States should not sell Taiwan more arms merely as a reaction to the recent U.S.-China conflict.

"Decisions on arms sales to Taiwan must be based on our national interests -- not Taiwan's, not China's," said Kerry, the top Democrat on the Senate Foreign Relations Committee's Asia panel. "In making those decisions we must assess not only Taiwan's defense needs and capacity to absorb new systems but also the impact on stability across the strait and Taiwan's long-term security."

Recent events will have no effect on the Taiwan arms sales, predicted Rep. Christopher Cox, R-Calif., a major voice in the House on China.

"The net effect is a wash," Cox said. "On the one hand, there could be reason to buckle down on security matters. There's also an equal and offsetting impulse to avoid overreacting, or further inflaming the situation. That leaves you essentially where you started: with an objective analysis" of Taiwan's defense needs.

A senior Bush administration official said Thursday it remains unclear how much agitation on weapons the anti-China forces will cause in Congress.

Not much, at least regarding arms sales to Taiwan, predicted Rep. Jim Leach, R-Iowa.

"Congress will support any administration decision in this area," said the chairman of the House International Relations subcommittee on East Asia and the Pacific.

National security adviser Condoleezza Rice said Thursday, "No one who has responsibility for making a decision has even looked at the Taiwan arms issue just yet."

"We will be getting recommendations about it, and the president will consider it in due course," Rice said on CBS' "Early Show." "And I'm certain that he will consider it the context of what it takes to help Taiwan defend itself."

Topping Taiwan's shopping list are four Arleigh Burke-class destroyers, priced at more than $1.2 billion apiece, equipped with missiles and the Aegis radar that can simultaneously track more than 200 targets. Taiwan is also requesting Kidd-class destroyers with radar systems just below the top-of-the-line Aegis, diesel submarines, and the Army's advanced Patriot anti-missile system known as PAC-3.

Bush will decide what weapons can be sold, and Congress will have 30 days to reject his decision. In that event, Bush could veto the rejection. If Congress failed to override the veto, Taiwan could buy whatever it wanted from Bush's list.