U.S. President Barack Obama on Monday nominated Army Gen. Martin Dempsey as the next chairman of the Joint Chiefs of Staff, replacing Navy Adm. Michael Mullen who is retiring at the end of September.

Brigadier General Martin E Dempsey takes a question from a journalist during a news conference at the US army headquarters in Baghdad in this February 2, 2004 file photograph. [Photo/Agencies]

In a White House announcement, Obama also named Adm. James Winnefeld, the commander of Northern Command, as the vice chairman of the Joint Chiefs of Staff. Army Gen. Raymond Odierno, currently in charge of the U.S. Joint Forces Command, was tapped to replace Dempsey as Army chief. All nominations must be confirmed by the Senate.

"With nearly 40 years in uniform, Martin Dempsey is one of our nation's most respected and combat-tested generals," the president said, calling on the Senate to confirm Dempsey's nomination "as swiftly as possible."

Dempsey, a veteran combat commander, assumed his current assignment as Army chief of staff on April 11, 2011. He had served in the first Gulf War and commanded the 1st Armored Division in Iraq from 2003 to 2004. From 2007 to 2008, he served as Deputy Commander and then Acting Commander of U.S. Central Command.

If confirmed by the Senate, Dempsey would be the first Joint Chiefs head from the Army since 2001.

The moves are the latest in a reshuffling of the Obama's national security team. Last month, Director of the Central Intelligence Agency Leon Panetta was nominated by the president to succeed Robert Gates as the next Defense Secretary, while David Petraeus, Commander of U.S. and NATO forces in Afghanistan, was tapped to head the CIA after Panetta's departure.

"It's essential that this transition be seamless and that we stay focused on the urgent national security challenges before us," said Obama.

Winnefeld will succeed Marine Gen. James Cartwright, long been rumored to be Obama's pick for the next Joint Chiefs head. He took his current job in May 2010, and had previously served as a NATO commander and on the Joint Staff.

Odierno, Dempsey's successor, assumed his current assignment in October 2010. The Joint Forces Command he is now heading is scheduled to be deactivated this summer.