"Pakistan possesses nuclear weapons. It has an unstable government and a dramatic rise of Islamic fundamentalism. Many people have called it ground zero as far as terror is concerned" Democratic Senator Diane Feinstein said at a Senate Sub Committee hearing on Energy.

"If you ask some of us what is the most threatening nuclear situation, we'd have to say it's Pakistan in terms of those nuclear facilities. The question I have is what steps can we take to confront this challenge to see that the weapons remain secure and to actually improve the situation in terms of stability of government and therefore, stability of the nuclear weapons programme," Senator Feinstein asked a senior administration official.

William Tobey, the Deputy Administrator in the Office of Defence Nuclear Non Proliferation of the National Nuclear Security Administration, in his reply said: "We've extended an invitation to Pakistan to join the global initiative to combat nuclear terrorism, which they have done. They have participated in an exercise in China. That initiative is aimed at drawing together nations to share best practices, essentially throughout the possible prevention and response cycle."