US President George W. Bush says the United States is locked in a struggle with guerrillas for the support of the Iraqi population as US troops pound rebel positions for a second night.
US national security adviser Condoleezza Rice, reflecting a new urgency in Washington born of increasing guerrilla violence, said it was important to find a way to accelerate a transfer of authority to the Iraqi people.
"They are, we believe, ready for it. And they have very strong ideas about how that might be done," she told reporters.
Heavy gunfire and explosions echoed across Baghdad as US forces pressed into the second day of Operation Iron Hammer, sweeps against suspected guerrilla targets designed to quell an increasingly bold and spreading insurrection.
General John Abizaid, leading US military efforts in Iraq, said resistance forces fighting US and allied troops numbered no more than 5,000, compared with 130,000 U.S. troops and 25,000 British, Polish, Italian and other forces.
Despite their relatively small numbers, the guerrillas have launched ever bolder attacks in Baghdad in the last 10 days, including night-time mortar attacks on the heavily fortified headquarters of the US-led administration.
Acknowledging the scale of the challenge facing the United States seven months after the fall of Saddam Hussein, Bush told reporters insurgents wanted to sow fear among Iraqis to undermine support for the occupation.
"That's the struggle. And we're going to prevail because, one, we've got a good strategy to deal with these killers; two, I believe by far the vast majority of Iraqis do understand the stakes and do want their children to grow up in a peaceful environment," Bush said.
The US president said he was working to overhaul plans for Iraq's transition to self government.
Washington's plan has been for the US-appointed Iraqi Governing Council to organise the writing of a new constitution, then hold elections before power is transferred.
Bush declined to confirm reports that after talks with the US administrator of Iraq, Paul Bremer, he had abandoned this strategy.
"What I'm interested in doing is working with Ambassador Bremer and the Governing Council to work on a plan that will encourage the Iraqis to assume more responsibility," Bush said in the Oval Office.
That would draw the US administration's policy closer to that of sceptical European allies.
French Foreign Minister Dominique de Villepin, whose government was critical of the US war on Iraq, said France was ready to help with the reconstruction once sovereignty was awarded to a provisional Iraqi government.
Guerrillas, believed to include Saddam supporters, foreign fighters and possibly al Qaeda, have killed 156 US troops since Bush declared major combat in Iraq over on May 1.