These are the most important weapons in the Pakistani arsenal, he said in a interview at Aspen Security Forum in Colorodo, according to a Pentagon statement issued on Tuesday.
At the same time, Mullen said United States is working hard to regain Pakistans trust after several years without a relationship, but its going to take time. US-Pakistan military relations, which ended in the 1990s were resumed after 9/11 terrorist attacks.
Elaborating on the safety of Pakistani nuclear weapons, he said, As much as we are focused on this [terrorism] threat - and the Pakistanis are more than they used to be - they see a threat in India and [having nuclear weapons] is their deterrent. They see this as a huge part of their national security.
About regaining the Pakistanis trust, Mullen said, Its not going to happen overnight. But, he added, Ive seen significant commitments in the whole of government.
Strong relations with Pakistan are important to stamping out terrorism in Afghanistan and Pakistan that threatens the US, Mullen said, noting that he recently returned from his 18th trip to Pakistan since becoming chairman.
I believe the leadership in Pakistan recognises the importance of how it all turns out in Afghanistan, he said. We are in agreement that Afghanistan needs to be stable and peaceful. How we get there and the long-term commitment is critical. Thats a huge part of the engagement strategy with Pakistan.
The US and NATO strategy in Afghanistan is to dismantle the leadership of al-Qaeda to make the terrorist group ineffective. And the al-Qaeda leadership resides in Pakistan, Mullen said.