Central Command oversees all US operations in Iraq and Afghanistan
US Defence Secretary Robert Gates has recommended the top military commander in Iraq, General David Petraeus, be appointed head of US Central Command.
CentCom covers an area from the Horn of Africa into central Asia and includes all operations in Iraq and Afghanistan.
Gen Petraeus's appointment is subject to the approval of the US Senate.
He would replace Navy Adm William Fallon, who stepped down in March after a reported split with President George
W Bush over his policy on Iran.
An article by Esquire magazine, titled The Man Between War and Peace, said he was opposed to the use of force against the Islamic Republic over its nuclear activities.
Adm Fallon said the report, while not true, had become a distraction.
At a news conference at the Pentagon, Mr Gates said the joint chiefs of staff had agreed that Gen Petraeus should be nominated as head of CentCom and "I am absolutely confident he is the best man for the job".
"The kinds of conflicts that we're dealing with, not just in Iraq, but in Afghanistan and some of the challenges that we face elsewhere in the region, and the Central Command area, are very much characterised by asymmetric warfare," he added.
"I don't know anybody in the United States military better qualified to lead that effort."
The 55-year-old has overseen since last year the "surge" of an additional 30,000 US troops in Iraq, which has been credited widely with improving security and helping reduce violence.
Mr Gates said Gen Petraeus would not leave Iraq until later summer or early autumn, if his appointment is confirmed, in order to ensure he had enough time for a proper handover.
Lt-Gen Ray Odierno, his deputy in Iraq and currently commander of the Army's 3rd Corps, has been nominated to replace him.
Mr Gates said Gen Odierno had gained plenty of experience as "Petraeus's right-hand man" in Iraq over the past year.
He said he hoped both appointments would be approved by the Senate by Memorial Day, which is on 26 May this year.
In a brief statement from Baghdad, Gen Petraeus said he was "honoured to be nominated for this position and to have an opportunity to continue to serve with America's soldiers, sailors, airmen, marines, coastguardsmen and civilians".