The Bush administration and the Senate continued to struggle to reach a compromise on legislation over the treatment of detainees, after a meeting between Sen. John McCain and President Bush's national security adviser on Wednesday failed to broker a deal.

The senator has proposed a ban on cruel, inhuman and degrading treatment of foreign terrorism suspects. Administration officials say torture is already illegal and some methods short of torture could help during crunch time when a prisoner could have vital information about an imminent attack.

Meanwhile, the House approved the Senate-passed ban in a 308-122 vote on a non-binding resolution that puts added pressure on House negotiators who oppose the measure and the White House that wants to avoid them.

The administration is seeking language in the bill that would offer some protection from prosecution for CIA interrogators accused of violating McCain's provision.

White House Press Secretary Scott McClellan said Wednesday that the request is not for an exemption.

"We are continuing to work with Senator McCain and his staff to find a good solution on how we move forward," McClellan said. "We're talking about the safety and security of the American people, and we're engaged in a different kind of war against a very dangerous enemy. ... There are already laws on the books that prohibit torture, both treaties and our own laws ... prohibit torture.

National Security Adviser Stephen Hadley told The Associated Press as he left McCain's Capitol Hill office after a meeting that lasted more than an hour Wednesday morning that "at this point, discussions are ongoing."

"We continue to chat," McCain, R-Ariz., said just before meeting with Hadley.

A compromise may be reached later this week, but the talks failed to bring the two sides together on Wednesday, congressional aides said. Still Sen. John Warner, R-Va., said Wednesday afternoon that he is "optimistic that progress will be made." Warner's counterpart in the House, Rep. Duncan Hunter, R-Calif., said negotiators were "very close" to reaching a compromise on the legislation.

The House resolution was sponsored by Rep. John Murtha, D-Pa., and puts the chamber on record in support of McCain's provisions. Endorsing the provisions were 200 Democrats, 107 Republicans and one independent.

"We cannot torture and still retain the moral high ground," Murtha, the senior Democrat on the House appropriations defense panel, said. "There can be no waiver to the use for torture. No torture and no exceptions."

Rep. Bill Young, R-Fla., the chairman of that panel, said the United States does not torture but that it's "important that we make it very clear that we are opposed to torture -- period." However, he said he was offended because the provisions would give terrorists too many protections

McCain has said he opposes the administration's request for protective language of interrogators, instead opting to include provisions similar to the Uniform Code of Military Justice. The language would allow accused civilian interrogators the ability to defend themselves if a reasonable person could have found they were following a lawful order about detainee treatment.

Two defense bills have been held up over the ban on mistreatment of prisoners and another provision standardizing the interrogation techniques used by U.S. troops.

Lawmakers want the bills passed by the House and Senate before the end of the year. GOP leaders are likely to push for action on the bills soon.

Karen Hughes, undersecretary of state for public diplomacy and public affairs, expressed confidence that McCain and Hadley would "reach consensus."

"The goal is the same here," Hughes said on CBS' "The Early Show." "The goal is to make it very clear that the United States is a nation of laws and that we operate our detainee policy within our laws, within our international obligations and without torture."

The Senate and House are also in disagreement over parts of the bill. The Senate passed McCain's provisions but they were not included in the defense bills approved by the House.

House leaders have held off moving toward a vote until they get their cue from the White House. After initially threatening a veto and trying to kill the provisions, the White House then switched gears to lobby for an exemption to the ban for CIA interrogators. But McCain balked at that, and it was taken off the negotiating table.

The senator has said he won't agree to changes that would undermine the provisions, which he argues are needed to clarify current anti-torture laws in light of abuses at Abu Ghraib in Iraq and allegations of misconduct by U.S. troops at the detention center at Guantanamo Bay, Cuba.

Meanwhile, the Defense Department denied Wednesday that the Pentagon is trying to complete guidelines on detainee interrogation before Congress could pass legislation that would ban cruel and inhuman treatment.

The manual defines treatment for detainees and outlines interrogation techniques. The manual, which is still being reviewed by Pentagon officials, explains guidelines such as how long detainees can be forced to sit or stand in certain positions.

The New York Times reported in Wednesday's editions that the Army has approved a new classified section that outlines interrogation techniques. Some Army officials said McCain, who spent five years in a POW camp in Vietnam and suffered abuse at the hands of the enemy, may not support some of those techniques.

The Pentagon said that "the implication in the story that this is some attempt to get around discussions that are taking place is just flat wrong and it's harmful," said Lawrence DiRita, a spokesman for the Pentagon.

The Pentagon denies that any DOD official is trying to push for new interrogation guidelines that would extend the limits on legal interrogation, Di Rita said.

"If there is a law passed, our activities will be consistent with the law," Di Rita said.

McCain too said the addendum is merely a draft, and Congress' decision on the bill's language will affect changes to the manual, not the other way around.

FOX News' Bret Baier and Nick Simeone and The Associated Press contributed to this report.