WASHINGTON — The Bush administration's proposal to bring leading terror suspects before military tribunals met stiff resistance on Thursday from key Republicans and top military lawyers who said that some provisions would not withstand legal scrutiny or do enough to repair the nation's tarnished reputation internationally.

Democrats, meanwhile, said they were inclined to go along with Senate Republicans drafting an alternative to the White House plan, one that would allow defendants more rights. That left Republicans to argue among themselves about what the tribunals would look like and threatened to rob the issue of the political momentum the White House hoped it would provide going into the closely fought midterm elections.

A day after President Bush unveiled the plan at the White House, senior administration officials said Bush was willing to negotiate with Congress about the shape of legislation to establish tribunals, which would replace those struck down in June by the Supreme Court.

The administration officials — who agreed to discuss sensitive internal administration deliberations in exchange for anonymity — said the decision to transfer high-level terror suspects from CIA prisons to military custody had been the result of months of secret debate at the highest levels of government. The officials said the change had been most vigorously championed by the State Department, under Condoleezza Rice, against some resistance from a range of officials, including Vice President Dick Cheney, who had defended the status quo, in which high-level al-Qaida leaders, including the alleged mastermind of the Sept. 11 attacks, have been held in secret CIA custody.

The 14 terror suspects recently transferred to the American detention center in Guantanamo Bay, Cuba, under the administration plan would face war-crimes trials if Congress approves the proposed tribunals. On Thursday, Rear Adm. Harry B. Harris Jr., the commander of the American detention facility, said the 14 prisoners had been registered for the first time with the International Committee of the Red Cross, but he would not say when the prisoners had arrived, whether they had arrived together, or how long he had known in advance that they were coming.

In Congress, Republican leaders said the House would vote on the president's proposal the week after next, and the chairman of the Armed Services Committee, Rep. Duncan Hunter of California, argued in favor of the administration's approach in a hearing on Thursday morning with military lawyers.

But the military lawyers argued back. And the Senate Republicans said there were still several areas of contention between them and the administration, chiefly, a proposal to deny the accused the right to see classified evidence shown to the jury.

Brig. Gen. James C. Walker, the top uniformed lawyer for the Marines, said no civilized country should deny a defendant the right to see the evidence against him, and that the United States "should not be the first."

Maj. Gen. Scott C. Black, the judge advocate general of the Army, made the same point, and Rear Adm. Bruce E. MacDonald, the judge advocate general of the Navy, said military law provided rules for the use of classified evidence, whereby a judge could prepare an unclassified version of the evidence to share with the jury and the accused and his lawyer.

Senate Republicans said the proposal to deny the accused the right to see classified evidence was one of the main points of contention remained them and the administration.

"It would be unacceptable, legally, in my opinion, to give someone the death penalty in a trial where they never heard the evidence against them," said Sen. Lindsey Graham of South Carolina, who has played a key role in the drafting of alternative legislation as a member of the Armed Services Committee and a military judge. "'Trust us, you're guilty, we're going to execute you, but we can't tell you why?' That's not going to pass muster; that's not necessary."

Bush announced his proposal for bringing terror suspects to trial on Wednesday as part of a round of speeches on national security aimed at drawing a sharp distinction between the two parties: Democrats as weak on terror, Republicans strong. The administration created its system of tribunals shortly after the terrorist attacks of Sept. 11, 2001, but the Supreme Court struck down those tribunals in June, saying that they violated the Constitution and international law.

Senior administration officials said the decision to acknowledge the secret CIA detention program, to move the 14 "high value" detainees to Guantanamo and to set up a new system for putting them on trial emerged from a committee Bush established in January, six months before a Supreme Court decision forced his hand on some of those issues.

The committee, run by J.D. Crouch, the deputy national security adviser, held more than 20 meetings in secret at the White House, and a half-dozen more higher-level sessions with Bush's national security team, which included Cheney, Rice, Defense Secretary Donald H. Rumsfeld and the director of national intelligence, John D. Negroponte.

While the White House on Thursday described those meetings as a largely harmonious effort to remake a detainee system that had created objections around the world, other officials said that Rice's State Department was often pitted against Cheney's staff.

"There were a range of opinions on a number of issues, but it's pretty fair to say that the State Department had been arguing for 18 months that we needed to put this whole thing on a strong legislative footing, and end the dispute with the allies," said one official who was part of the process. "And there were others, from the vice president's office to some in the Justice Department and the White House, who wanted to maintain the status quo."

The standoff was broken by the Supreme Court's decision in June in the Hamdan case, which took many in the White House by surprise, the officials said.

Administration lawyers on Capitol Hill said Thursday that the military trials now proposed by the administration were markedly different from the previous system, and would pass court scrutiny.

Among other changes, the proposal sets up tribunals overseen by a judge who could not also serve as part of the jury. Defendants would be given two appeals, and could not be tried twice.

But Senate Republicans remained divided over the White House proposal.

On one side, Graham and Sens. John McCain of Arizona and John Warner of Virginia have argued that the system must provide enough guarantees of fairness that the nation would feel comfortable having American troops tried under it. This is important, they argue, to repair a national reputation that has been damaged internationally by revelations of abuse at Guantanamo Bay and at Abu Ghraib prison in Iraq, and to set a model for how other countries might try American troops.

On the other side, Sens. John Cornyn of Texas and Jeff Sessions of Alabama have shown more inclination to endorse the president's proposal. Cornyn said after a round of meetings on Thursday that he still supported the president's approach on classified evidence, but that he hoped the differences could be bridged. "We're trying," he said.

Democrats have essentially said they would back Warner, Graham, and McCain, leaving the Republicans to lead the fight against the administration, and allowing the Democrats to avoid political fallout from challenging the administration while maintaining their criticism of the administration's handling of the war in Iraq.

"I think you're looking for a fight that doesn't exist," the minority leader, Harry Reid of Nevada, told reporters. In testimony on the Hill, an administration lawyer stood firm on the importance of denying suspects the right to know the classified evidence against them.

"In the midst of the current conflict, we simply cannot consider sharing with captured terrorists the highly sensitive intelligence that may be relevant to military-commission prosecutions," said the lawyer, Steven G. Bradbury, the acting assistant attorney general in the Office of Legal Counsel.

Contributing: David E. Sanger