A Senate committee on Thursday defied warnings from President Bush and passed a bill defining the treatment of terror-suspect detainees.

The move sets up battle between the president and his party over how to conduct the War on Terror.

The Senate Armed Services Committee voted 15-9 in support of a bill sponsored by Chairman Sen. John Warner, R-Va. The bill seeks to address a Supreme Court ruling that says the current system that handles detainees is unlawful and must be changed by Congress.

Three other Republicans joined all 11 panel Democrats in supporting the measure: Sens. John McCain of Arizona, Lindsay Graham of South Carolina and Susan Collins of Maine.

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The key differences between the Warner bill and what the administration wants are definitions of how detainees should be treated under the Geneva Conventions, and access to classified evidence during proposed military commissions. The Geneva Conventions is a treaty that sets international standards for the treatment of prisoners of war.

Warner's bill, unlike the one favored by the president, would avoid setting up a separate legal category for so-called CIA interrogation techniques deemed as aggressive. It would also require that classified evidence given to juries also to made available to defendants.

Meanwhile, nine retired federal judges on Thursday accused the Bush administration and Congress of trying to deprive detainees at Guantanamo Bay, Cuba, of the most basic legal right. Part of the legislation under debate on Capitol Hill would strip federal courts of the power to hear detainees' challenges of their treatment and indefinite detention at Guantanamo Bay.

"Depriving the courts of habeas jurisdiction will jeopardize the judiciary's ability to ensure that executive detentions are not grounded on torture or other abuse," the judges wrote in a letter to Congress.

Congress and the administration would be skating "on thin constitutional ice" in depriving courts of their power to hear detainees, the letter added.

During the hearing Thursday, Warner said he would seek a bill that could contrast with the administration.

"It is my fervent hope that whatever the Congress does, the legislation will be able to withstand further scrutiny, review by the federal court system, and indeed the Supreme Court of the United States," he said. "It would be a very serious blow to the credibility of the United States — not only within the international community, but here at home — if legislation that was prepared by the Congress, signed by the president, failed to meet a second Supreme Court review."

Sen. Carl Levin, D-Mich., said that "whatever we do must protect our troops." He said any bill passed should meet international standards, so if U.S. troops face detention proceedings overseas, the U.S. can insist for fair and humane treatment.

"That means in my book that we must not modify Geneva, but enforce Geneva," Levin said.

Warner also believes the administration proposal could also potentially put U.S. troops at risk.

But earlier in the day, Bush said he would "resist" any bills that do not clarify the laws over detainees. Republicans said portions of the Geneva Conventions can be unclear and could cause Americans to be wrongfully prosecuted under war crimes.

Sen. John Cornyn, R-Texas, said the committee's vote "will cause the [detainee interrogation] program to shut down. This is the very same program that the president discussed last week that has led to 50 percent of the intelligence we've achieved in detecting and deterring and disrupting terroist activities."

To the argument that the Bush plan could endanger U.S. troops, Cornyn earlier noted that Al Qaeda doesn't take prisoners. "The prisoners they do take they behead," he said.

Bush lobbied lawmakers on Capitol Hill Thursday morning to push legislation allowing tougher interrogation of terror suspects, and vowed to fight opposition within his own party.

"I will resist any bill that does not enable this plan to go forward," Bush told reporters back at the White House after his meeting.

The White House on Thursday said the alternate approach was unacceptable because it would force the CIA to end a program of using forceful interrogation methods with suspected terrorists.

"The president will not accept something that shuts the program down," said White House spokesman Tony Snow.

Speaking with FOX News after the vote, Senate Majority Leader Bill Frist downplayed suggestions that the bill's passage through committee represented a schism in his party. Instead, he said, the success so far for Warner's bill was just part of the legislative process.

"We will take a bill to the floor and we will debate. Right now these are huge issues. We're talking about the safety and security of the American people. They deserve debate. They will have that debate, and a decision will be made," Frist said

He denied that it was a foregone conclusion that he would not bring up Warner's bill next week, when the detainee issue is expected to hit the full Senate. But he said he was "absolutely" leaning toward the prospect of bringing up the president's version of the bill.

Frist added: "A lot of people are trying to make this into, sort of, intraparty battles and the like. Luckily everybody's goal is exactly the same, and that is, how we can have a safe and effective program that provides the information that will protect us, our saftery and security in this new post-9-11 world?"

Powell Chimes In

Bush's calls to follow his lead came as a former member of his Cabinet aligned himself with the group of Republicans seeking to block the president's plan.

Former Secretary of State Colin Powell, in a letter sent to McCain, said Congress must not pass the president's proposal to redefine U.S. compliance with the Geneva Conventions.

"The world is beginning to doubt the moral basis of our fight against terrorism," wrote Powell, who served under Bush and is a former chairman of the Joint Chiefs of Staff. "To redefine Common Article 3 [of the Geneva Convention] would add to those doubts. Furthermore, it would put our own troops at risk."

Snow, asked if Powell was confused about the White House's goals, said "yes."

Pressed further on why Powell might write such a letter, Snow said: "We didn't hear from him, so I don't know."

"There's all kinds of letters coming out," Bush told reporters, reacting to a question about Powell's letter. "We want to work with Congress to make sure the program can go forward."

Bush, who conferred behind closed doors with the House Republican Caucus, said he would "continue to work with members of the Congress to get good legislation."

"I reminded them that the most important job of government is to protect the homeland," he told the press after the session. Bush was accompanied to the Hill by Vice President Dick Cheney and White House adviser Karl Rove.

On Wednesday, the White House arranged for a conference call with reporters so National Intelligence Director John Negroponte could argue that Warner's proposal would undermine the nation's ability to interrogate prisoners.

"If this draft legislation were passed in its present form, the director of the Central Intelligence Agency has told me that he did not believe that the [interrogation] program could go forward," Negroponte said.

Bush also was pushing Thursday for changes that would give legal status to the administration's warrantless wiretapping program.

It was approved on a party-line vote by the Senate Judiciary Committee on Wednesday, but is stalled in the House amid staunch opposition from Democrats and some Republicans concerned that the program violates civil liberties.

FOX News' Trish Turner and The Associated Press contributed to this report.