A conference later on Saturday in Baghdad will bring diplomats from Iraq and its neighbors - including Syria and Iran - into discussions with the permanent members of the United Nations Security Council .
Iraqi Prime Minister Nouri al-Maliki said Friday the international conference shows the situation in Iraq is improving.
Mr. Maliki spoke during a rare excursion outside Baghdad's green zone during which he greeted bystanders and police.
A top US diplomat participating in the conference has said the United States is prepared to raise concerns about Iraq directly with Iranian and Syrian representatives.
The US is concerned that Iranian weapons are being used by insurgents to attack U.S. troops in Iraq. Washington also wants Syria to stop the flow of foreign fighters and weapons across the Syrian border into Iraq. Iran has said the current major problem is the presence of US forces in Iraq.
Meanwhile, news reports say the leader of an al-Qaida-linked group was captured in the Abu Ghraib area on the outskirts of Baghdad. The reports said Abu Omar al-Baghdadi, the leader of the group called Islamic State of Iraq, was arrested Friday. U.S. officials said they had no information on the report.
Separately, the US commander of coalition forces in northern Iraq says he has asked for more troops to be moved to Diyala province - to keep pressure on insurgents who might use the area as a refuge or base.
Also on Friday, officials reported the death of one US Marine and 13 insurgents. Iraqi and U.S. forces are in the third week of a security crackdown in the Iraqi capital.