McCain, a member of the bipartisan panel, said such powers would give commission "certain credibility," and voiced hope an agreement would be reached to obtain it.

Asked on ABC's "This Week" if he would continue to serve on the commission if it did not get subpoena power, McCain, a maverick, said, "I'd hate to throw down a gauntlet like that."

"I am hopeful and somewhat optimistic that this could be worked out," McCain said.

Bush, under pressure from Democrats and Republicans, created the commission on Feb. 6 to determine why no weapons of mass destruction have been found in postwar Iraq. The Bush administration cited the threat of such weapons programs as a primary reason for the Iraqi war.

"It's clear that there were intelligence failures," McCain said. "But that does not in any way, in my view, remove the justification for removing Saddam Hussein from power."

Bush gave the commission until March 31, 2005, to report back, meaning results will not be known until after November when voters decide whether to give him a second term.

McCain said, "I think it needs subpoena power, and I think it needs to look at every aspect of the intelligence situation, including how intelligence was used."

"It's not because I don't trust the administration. There are other agencies outside government and other governments outside the United States that probably we need to have information from," McCain said.

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