A series of bombs killed at least 43 people in and near Baghdad on Saturday, police said. In the deadliest attack, a car bomb struck an Iraqi police checkpoint in south-west of Baghdad, killing at least 12 people and wounding 38, police said. Earlier, another car bomb targeting Iraqi army and police killed 11 people.
In a fresh reminder of the huge task Maliki faces despite a claim by Iraq's national security adviser that al Qaeda's days were numbered, militants hit security forces across the capital and bombed at least two crowded markets, including one in central Baghdad that left six people dead.
In the town of Mahmudiya just south of the capital, a car bomb targeting an Iraqi army checkpoint killed seven people.
US military helicopters and divers searched for two US soldiers missing after an attack on Friday in which one American soldier was killed in the insurgent bastion of Yusufiya in the "Triangle of Death" south of Baghdad.
More than 2,500 US soldiers have died in Iraq since the US-led invasion in 2003.
Bush said on Saturday the United States had gone too far to abandon Iraq now and encouraged other nations to make good on $13 billion in pledges to help the new Iraqi government.
"It is vital for the Iraqi people to know with certainty that America will not abandon them after we have come this far," Bush said in his weekly radio address.
Bush gave no hint of any imminent drawdown of the 129,000 US troops in Iraq despite domestic political pressure to do so before crucial congressional elections in November.
"We face determined enemies who remain intent on killing the innocent, and defeating these enemies will require more sacrifice and the continued patience of our country," he said.