U.S. Vice-President Joe Biden arrived in Baghdad on an unannounced visit this morning, a day before the formal end of combat operations in Iraq.
President Obama is to address the nation on Tuesday on Iraq and Afghanistan.
There are now fewer than 50,000 troops on the ground in Iraq, down from 160,000 at the end of President George W. Bush's administration. The remaining troops will focus on providing assistance and training to the Iraqi military.
Biden will also meet with Iraqi officials who have been struggling to form a government after elections in March resulted in a hung parliament, including Iraqi President Jalal Talabani, Vice President Tariq Hashimi, Vice President Adil Abd Mahdi and Prime Minister Nouri Maliki.