"Please let it not be thought that the same proliferation activity will start again," Musharraf told the NBC network in an interview in Islamabad. "Never. That will never happen."

He was responding to questions about his handling of the confession last week by Abdul Qadeer Khan, revered as the father of Pakistan's atomic bomb, that he had leaked secrets to Libya, North Korea and Iran as head of Pakistan's nuclear program from the 1970s.

Musharraf quickly pardoned Khan and rejected calls for an independent inquiry into the military's role in the nuclear leaks.

Asked by NBC Nightly News anchor Tom Brokaw about charges that this amounted to a whitewash, Musharraf said:

"I disagree with it absolutely. The dilemma is: he's a great man, he's a hero, and he's a hero of every individual in the street. Yet he has done something which could bring harm to the nation. Now how do I deal with it?" Musharraf said.

"One must understand the reality. There's an international perception. There's a domestic perception," Musharraf said.

The Pakistani leader said he would back any move by the United States to put more troops into Afghanistan to turn up the pressure on al Qaeda. But he stressed US forces hunting al Qaeda and Taliban fighters would not be allowed to cross into Pakistan.

"Not only is it not possible, but it's not required," Musharraf said. "We have developed a very effective quick reaction force. A mobile hard-hitting, quick reaction force. That is what is required and we are capable of doing all of that."

A Pakistani government official said on Sunday that Secretary of State Colin Powell was expected to visit Pakistan and meet Musharraf soon to discuss the nuclear proliferation issue.