The two senior members of the U.S. Senate Armed Services Committee say they witnessed what they call a "great deal of apprehension" by the Iraqi government to shed sectarian divisions.
Democrat Carl Levin and Republican John Warner have just returned to Washington from a two-day visit to Iraq.
They say the surge of U.S. forces has made parts of Baghdad and its immediate vicinity more secure and given Iraqi politicians more opportunities to compromise.
But the senators say they are not optimistic about the chances for compromise. They say they believe the politicians are afraid to end sectarian biases and unify.
Senators Levin and Warner said they told Iraqi leaders that the American people and Congress are running out of patience with the political process and that the need to compromise is urgent.