Leon Panetta will need to be confirmed in the position by the US Senate [AFP]

CIA director Leon Panetta will become US defence secretary and be replaced at the spy agency's helm by General David Petraeus, current head of military operations in Afghanistan, ABC News reported on Wednesday.

Panetta, a 72-year-old Democratic politician, lawyer and professor will take over from Robert Gates following his planned retirement this year. 

President Barack Obama will also nominate veteran diplomat Ryan Crocker as the next US ambassador to Afghanistan, according to an NBC News report.

The positions will require Senate confirmation.

A shuffling of top national security jobs has been an object of speculation for weeks, says Reuters.

Source: Al Jazeera and agencies