U.S. Defense Secretary Robert Gates is in Iraq on a previously unannounced visit.
Gates and the top U.S. commander in Iraq, General Ray Odierno, met with Iraqi Prime Minister Nouri al-Maliki in Baghdad Tuesday.
The three were expected to discuss the U.S. military's evolving role in Iraqi security, and also arms sales to supply Iraq with security equipment after the departure of U.S. troops.
Gates flew to Baghdad after a stop in southern Iraq at a U.S. command post in Tallil.
Gates also is expected to visit Iraq's autonomous Kurdish region in an attempt to bridge the divide between Iraq's ethnic Kurds and majority Arabs.
The dispute between Iraqi Kurds and Arabs over oil-rich territory has threatened to erupt into new violence, even as the U.S. military prepares to withdraw its forces from Iraq by the end of 2011.
High-level U.S. officials are visiting the Middle East Tuesday as part of a new U.S. diplomatic push for peace in the region.
Gates flew to Iraq from Jordan, where he held talks with King Abdullah Monday. After that meeting, Gates warned Iran that the U.S. will push for tough sanctions if Tehran does not respond to Washington's offers to discuss Iran's nuclear program.
Some information for this report was provided by AFP and AP.