The most divisive issue is a timetable for the withdrawal of U.S. troops from Iraq, Abdel Kareem al-Samarraie told Voices of Iraq. He said the Iraqi government wants 2011 as a hard date, but Washington has refused.

Samarraie is a member of the Accordance Front, which holds 38 seats in parliament and sits on the Security and Defense Committee in parliament.

"Differences revolve around a schedule of the withdrawal of U.S. forces from Iraq as well as their powers and the description of these troops," he said.

Other issues on the table include immunity from Iraqi law for U.S. troops and whether the United States will maintain permanent bases in Iraq.