Obama backs Carter for defence role
President Barack Obama has backed Ashton Carter to oversee the sprawling Defence Department, heralding his new nominee as one of the country's "foremost national security leaders".
The President announced Mr Carter's nomination during a ceremony at the White House. A Pentagon veteran who is seen as a centrist, Mr Carter is expected to be easily confirmed by the Senate, putting him at the helm of a department moving back into military conflict in the Middle East even as it grapples with budget cuts.
The leadership shake-up at the Pentagon marks the only major change President Obama has made to his national security team during his second term.
While White House officials have not fully ruled out other changes, Mr Obama appears highly unlikely to replace national security advisor Susan Rice or White House chief of staff Denis McDonough, who plays a significant role in foreign policy decision-making.
In discussing the Pentagon post with Mr Carter, the President said he emphasised the need "to make smart choices, precisely because there are so many challenges out there".
Mr Carter, a widely respected physicist and academic, has won praise from some Republicans, suggesting he will face a smooth Senate confirmation. Mr Carter would replace Chuck Hagel, who resigned under pressure last week after a bumpy tenure.