"We welcome today's ratification by Iraq's Presidency Council of the Strategic Framework Agreement and Security Agreement," U.S. Ambassador to Iraq Ryan C. Crocker and U.S. Army Gen. Ray Odierno said in a statement issued from Baghdad.

The Status of Forces Agreement provides that U.S. combat forces will leave Iraqi cities and towns by next summer and be completely out of Iraq by the end of 2011.

The agreement will take effect Jan. 1, the day after a U.N. mandate on international military presence in Iraq expires.

Crocker and Odierno, commander of the multinational forces in Iraq, said in the statement the United States would support Iraq's request before the U.N. Security Council for continued protection of the country's assets. They said the United States also anticipated stronger cooperation on issues such as economics, energy, health and the environment.

"And we look forward ... to the continued reduction in U.S. forces and the normalization of bilateral relations as two sovereign and co-equal nations," the two said in the statement.