Gen. George W. Casey, Jr. (search), the Army vice chief of staff, has been nominated for a newly created post that would make him the top U.S. commander and only four-star general in Iraq (search).

The nomination, which had been expected, was announced by the Pentagon (search) along with several other major command assignments, including Navy Vice Adm. Timothy J. Keating to be commander of Northern Command (search), the military command that was created after the Sept. 11, 2001 terrorist attacks. Keating was the commander of naval operations during the initial phase of the Iraq war.

The nominations have to be confirmed by the Senate.

Lt. Gen. Ricardo Sanchez (searchis currently the top American commander in Iraq. His role in the Abu Ghraib prisoner abuse (searchcase has come under question recently, and although there is no accusation against him, senior Pentagon officials believed he could not be confirmed quickly by the Senate for the newly created position of commander of Multi-National Forces Iraq (search). Casey, who has been Army vice chief only since last October, is not expected to encounter Senate opposition.

As a four-star general in Iraq, Casey would be responsible for overseeing the U.S.-led military operation and interacting with the new Iraqi government that takes over June 30 as well as the U.S. ambassador in Baghdad, John Negroponte (search). A three-star, Lt. Gen. Thomas F. Metz, would manage day-to-day military activities.

Gen. John Abizaid (search), head of Central Command (search), will remain the top military officer responsible for the Iraq mission, although he is based in nearby Qatar and also has responsibility for U.S. military operations in Afghanistan and other countries in that region.

Replacing Casey as Army vice chief of staff would be Lt. Gen. Richard Cody (search), who currently is the Army deputy chief of staff for operations. Cody was nominated for promotion to four-star rank.

Among other command assignments announced Tuesday:

— Marine Corps Lt. Gen. James E. Cartwright to be promoted to four-star rank and be commander of U.S. Strategic Command.

— Navy Vice Adm. John B. Nathman to be appointed to the rank of admiral and assigned as vice chief of naval operations, the Navy's No. 2 position in the Pentagon.

— Marine Corps Maj. Gen. John Sattler to be given a third star and assigned as commander of the 1st Marine Expeditionary Force, replacing Lt. Gen. James Conway, who has held the position since November 2002. The 1st Marine Expeditionary Force (search) was the Marine element of the U.S. ground force that invaded Iraq in March 2003 and toppled the Saddam Hussein regime in Baghdad. Sattler is currently the director of operations for Central Command, based in Doha, Qatar.