Sept. 3 (Bloomberg) -- President George W. Bush arrived in Iraq on an unannounced trip to an air base in the country's Anbar province ahead of a progress report on the war that Congress is set to get next week.

Bush today made his third visit to Iraq on the way to the Asia-Pacific Economic Cooperation forum in Sydney. Over the next two weeks the U.S. Congress will be intensifying the debate on Bush's strategy in the conflict and the efforts of Prime Minister Nuri al-Maliki's government to meet benchmarks toward unifying the nation.

An assessment by U.S. intelligence agencies released Aug. 31 concluded that Iraq's political leaders still can't govern effectively even as the addition of 30,000 more U.S. troops this year is helping curb sectarian violence. The report has increased pressure on Bush from congressional Democrats and some Republicans, who are calling for the administration to begin a gradual withdrawal of forces.

The president left Washington in secrecy last night and Air Force One, a specially configured Boeing 747-200B aircraft, arrived at the al-Asad air base about 3:45 p.m. local time.

Bush has made two other surprise visits: Nov. 27, 2003, on Thanksgiving Day, and the other on June 13, 2006, a week after a U.S. air strike killed Abu Musab al-Zarqawi, al-Qaeda's leader in Iraq.

The president, in recent speeches to U.S. military veterans, has signaled he wants to keep his 30,000 troop-buildup in place to defeat insurgents and terrorists amid some signs that security conditions are improving, though no final decisions have been made.

Progress Report

Bush's trip comes as the administration is preparing for congressional testimony by Army General David H. Petraeus, the top U.S. commander in Iraq, and Ambassador Ryan C. Crocker the week of Sept. 10. The president is set to deliver a status report on the war, mandated by lawmakers, by Sept. 15.

Five years and six months into the war, Bush has characterized progress toward stability in Iraq as frustrating and slow. Still, there has been a reduction in violence in some areas, and the struggling Maliki government has passed about 60 pieces of legislation that both the Iraqis and U.S. officials say are crucial to achieving political goals.

Democrats, who hold majorities in the House and Senate, plan two weeks of hearings in the House and Senate that includes the testimony of Petraeus and Crocker as well as the recently published National Intelligence Estimate on Iraq, a report by the independent Government Accountability Office and retired Marine General James Jones.

`Failed Strategy'

``While the president continues to stay the course and ask Americans to pay for his failed strategy in Iraq, Democrats will continue to push for a new direction in Iraq to protect our troops and make America more secure,'' Senate Democratic Leader Harry Reid and House Speaker Nancy Pelosi said in a joint statement over the weekend.

The U.S. has about 162,000 troops in Iraq, including the 30,000 soldiers and Marines Bush ordered deployed there this year. The full contingent of reinforcements has been in Iraq a little more than two months and the president has argued they need enough time to quell the sectarian and terrorist violence that has wracked the country.

More than 3,730 U.S. military personnel have died in Iraq, at least 3,061 of whom were killed in action. More than 27,600 have been wounded, 12,429 of them so seriously that they couldn't return to duty, according to Defense Department figures.

Pentagon Visit

Bush went to the Pentagon on Aug. 31 to get reports from the Joints Chiefs of Staff and top military advisers about troop strength, the effect of 15-month deployments in Iraq on military personnel and the global condition of U.S. forces.

``The stakes in Iraq are too high and the consequences too grave for our security here at home to allow politics to harm the mission of our men and women in uniform,'' Bush said in a written statement afterward. ``It is my hope that we can put partisanship and politics behind us and commit to a common vision that will provide our troops what they need to succeed and secure our vital national interests in Iraq and around the world.''

To contact the reporter on this story: Roger Runningen in Baghdad at rrunningen@bloomberg.net

Last Updated: September 3, 2007 08:23 EDT