“I’m not going to try to be popular and change principles to do so,” Bush said in a television interview that aired on Sunday night.

Digging in for confrontation, Bush and Vice President Dick Cheney say they will not budge from sending more US troops to Iraq no matter how much Congress opposes it. “I fully understand they could try to stop me,” Bush, a Republican, said of the Democrat-run Congress. “But I’ve made my decision, and we’re going forward.”

As the president talked tough, lawmakers pledged to explore ways to stop him.

“We need to look at what options we have available to constrain the president,” said Democratic Senator Barack Obama, a possible White House candidate in 2008. Democrats remain wary, though, of appearing as if they do not support American troops.

A defiant Cheney, meanwhile, said Democrats offered criticism without credible alternatives. He pointedly reminded lawmakers that Bush is commander in chief. “You cannot run a war by committee,” the vice president said of congressional input.

The aggressive White House reaction came as the House and Senate prepare to vote on resolutions opposing additional US troops in Iraq.

As the White House watched even some Republican support peel away from the war plan, it went all-out to regain some footing.

Bush gave his first interview from Camp David, airing on Sunday night on CBS’ “60 Minutes.” It was his second opportunity in five days to explain on prime-time television why he thinks adding US troops can help stabilise Iraq and hasten the time when American soldiers can come home. He addressed the nation from the White House last Wednesday evening.