Describing the assassination of Benazir Bhutto [Images] as an 'utter shock', Pakistan president Pervez Musharraf [Images] has denied any hand in the killing of the former premier and said nobody should be assigned any blame until investigations are over.

In an interview on CBS News' Sixty Minutes show, Musharraf maintained that he had personally told Bhutto that she was under threat and that under the circumstances, the Pakistan People's Party leader should not have done the things she did on that fateful day in December.

"This is unfortunately a very baseless allegation," Musharraf said of the possibility that he had a hand in the killing of Bhutto. "Nobody has a right to blame anyone for killing anyone unless they have the proof," he said.

"Why would I be informing her about all these intelligence reports that we have against her, the threat to her? Why would I be doing that? I can't prove my innocence legally. But I can prove it only through what I stand for as a person," he said, adding, "There's no real protection against a suicide bomber".

Musharraf blamed the Al Qaeda [Images] for Bhutto's assassination, particularly local extremist Beitullah Mehsud, who operates out of Pakistan's lawless tribal region.

Regarding Al Qaeda supremo Osama bin laden, Musharraf said his administration was not particularly looking for him as there was 'no proof' he was in Pakistan.

"We are fighting extremism. We have arrested or eliminated about 700 Al Qaeda leaders. Only Pakistan has done it. Who else, which other country has done this?" he boasted.

When countered by his questioner that no other country had bin Laden, Musharraf responded, "No, I don't accept that at all. There is no proof whatsoever that he is here in Pakistan".

Coverage: Benazir Bhutto Assassinated

"We are not particularly looking for him (Laden) but we are operating against terrorists and the Al Qaeda and militant Taliban. And in the process, maybe we are looking for him also, if he's here," Musharraf said.

Stressing that the assassination of Bhutto came as an 'utter shock', Musharraf said his relationship with the slain former premier was one of ups and downs.

"Up and down. It wasn't constant. I had asked her not to come before the election. Is said we could make an arrangement and she could come after the election, to which she agreed. But then she decided to come all of a sudden. It upset me a little," Musharraf said, making the point that he was not particularly happy that Bhutto did not stick with the agreements they made.

Musharraf said the PPP leader used to 'change the goalposts frequently, depending on the ups and downs in the country', and on many occasions she annoyed him but 'on many other occasions, she was positive'.

"I think in such a situation, it's not your personal likes and dislikes. It's more for the nation that I thought one has to interact with her. I wouldn't say I didn't like or dislike her. I didn't have any kind of personal friendship with her," Musharraf said.

Musharraf said that Bhutto made a mistake by going to the area where she was killed by ignoring warnings that 'there's a likelihood of a suicide attempt'.

"We asked her not to go. She insisted on going. We stopped her. And we received so much flak from all over the world, from the media, from Western media," the Pakistani President said.