Adm. Mike Mullen, chairman of the US Joint Chiefs of Staff, warned in an interview with CNN on Sunday that Iran probably already has all it needs to build a nuclear bomb.
Asked if Iran has enough nuclear material to field an atomic weapon, Mullen said: "We think they do, quite frankly."
The admittance confirmed what top Israeli officials had been warning for months - that time for diplomatic measures for dealing with Iran's nuclear program has all but run out, and that more forceful options must be considered.
Appearing to contradict Mullen, US Secretary of Defense Robert Gates said in a weekend interview with NBC's Meet the Press that the Obama administration believes Iran is "not close to a [nuclear] weapon at this point, and so there is some time."
US President Barack Obama made eschewing the military option and instead engaging in dialogue with Iran over its nuclear ambitions a key component of his election campaign.