"And we know that the best way to honour the lives that have been given in this struggle is to complete the mission, so we will stay in the fight until the fight is won," the president said in a weekly radio address.

The assurance came amid increasing demands from Democrats and some Republicans to produce a specific strategy for handling the conflict that would map out a way to begin pulling out about 140,000 US troops currently fighting in Iraq.

An recent ABC News/Washin-gton Post poll showed 53 percent of Americans now believed the war was not worth fighting.

The survey also indicated 56 percent disapprove of Bush's handling of Iraq, including 44 percent who "strongly disapprove."

But Bush insisted that "all our troops and their families can know that the American people are behind them."

The president repeated his earlier argument that US forces must take the fight to terrorists overseas so that Americans don't have to face them at home.

He also argued the Iraq war stemmed from principles laid out by America's founding fathers in the Declaration of Independence that proclaimed an individual's universal right to freedom.

"By freeing millions from oppression, our armed forces are redeeming a universal principle of the declaration that all are created equal, and all are meant to be free," he said.