US Vice President Dick Cheney, an architect of the US-led invasion of Iraq, made an unannounced visit to Baghdad today to assess the success of a troop build-up five years after the war began.
Mr Cheney arrived as Republican candidate John McCain, who will be the Republican choice in November's presidential election, was meeting Iraqi leaders as part of a Senate Armed Services Committee fact-finding mission.
"Especially significant is to be able to return this week to mark the fifth anniversary of the beginning of the campaign that liberated the people of Iraq from Saddam Hussein's tyranny," Mr Cheney said after meeting Prime Minister Nuri al-Maliki.
Like McCain, Mr Cheney is in Iraq as part of a wider tour to the Middle East. Mr Cheney will also visit Saudi Arabia, Jerusalem, the Palestinian territories, Turkey and Oman on a nine-day tour.
Both men have been staunch supporters of a US troop build-up that Washington says helped drag Iraq back from the brink of all-out sectarian civil war between majority Shia and minority Sunni Muslims who were dominant under Saddam.
"I'm happy to say Americans are more and more understanding of the success of this strategy of the surge," McCain, referring to the build-up, told US soldiers in volatile Mosul in Iraq's north on yesterday, according to a video released by the military.
Mr Cheney was met on his arrival in Baghdad by General David Petraeus, the commander of US forces in Iraq. He last visited Baghdad in May 2007, a month before the deployment of an extra 30,000 troops was completed.
US military say attacks across Iraq have fallen by 60 per cent since last June, when the troop build-up was completed, but there has been a spike in violence since January.
Neighbourhood security units set up by mainly Sunni Arab tribal leaders and a ceasefire ordered by anti-US Shia cleric Moqtada al-Sadr for his Mehdi Army militia have also contributed to bringing down violence, the US military says.
Violence remains a daily threat despite the security gains. Roadside bombs and a minibus packed with explosives killed four people, including a policeman, and wounded 13 others in four attacks across Baghdad, police said. Neither Mr Cheney nor Mr McCain were in the area at the time.
A senior US administration official said before Mr Cheney's trip that Middle East leaders would be interested in seeing what conclusions he draws now compared with a year ago and that it was expected he would say progress is being made.