WASHINGTON, Feb 1: Chairman of the US Joint Chiefs of Staff, who plans to visit Pakistan later this month for talks with the new army chief, said on Friday that he could not disclose whether it were Pakistani or American troops who killed a top Al Qaeda figure earlier this week.

“I’m not going to talk any more about the operational side of this, of how that in fact occurred,” said Admiral Michael Glenn Mullen.

Abu Laith Al Libi, one of Osama bin Laden’s top five lieutenants, was killed in North Waziristan on Tuesday. Earlier reports said Libi was killed by a missile fired by a US drone.

During a special briefing at the Pentagon, Admiral Mullen also said that so far he had not seen any indication to suggest that support for President Musharraf in the Pakistani military had declined since his retirement.

He told the briefing that he planned to visit Islamabad soon for talks with Gen Ashfaq Kayani and “the rest of the leadership” for talks on America’s commitment to help Pakistan fight extremists.

“We’re very committed to working with the Pakistanis on this,” he said, adding that during this visit he would like to “establish a personal relationship” with Gen Kayani.

Admiral Mullen said he also wanted to “make sure that I understand his concerns and in fact work very hard to support them”.

Diplomatic sources in Washington say that US Defence Secretary Robert Gates may also accompany Admiral Mullen, but the Pentagon has not yet confirmed the secretary’s visit.

The top US commander also dispelled the impression that Washington wants to take unilateral actions in Pakistan’s tribal areas. “We will only do what is requested by Pakistan,” he said.

Last week, Secretary Gates and Admiral Mullen told a similar briefing that if Pakistan agreed, the US would like to conduct joint operations with Pakistani troops in the tribal areas.

President Musharraf, however, has rejected the proposal, saying that he does not want foreign troops on Pakistani soil.

Asked if the US offer was still valid, Admiral Mullen said: “Should the Pakistani government want to have that kind of assistance, then, clearly, we could do that. But that’s really up to them.”

He said this was another issue he would discuss with the Pakistani leadership “to see where they really are … and we can assist where asked and we’re going to have to work that over time.”

The admiral said the elimination of a key Al Qaeda figure like Libbi “is a very important outcome” in the war against terrorism, but the US remained concerns about the presence of alleged Al Qaeda safe-havens in Pakistan’s tribal region.

Admiral Mullen rejected the suggestion that the presence of people like Libbi inside Pakistan created the possibility that the extremists might one day seize the country’s nuclear weapons.

“I’m very comfortable that the nuclear weapons in Pakistan are secure and that the Pakistani leadership has taken steps to ensure that security,” he said.

Asked if he would discuss the security of Pakistan’s nuclear weapons with Gen Kayani when he meets him, the admiral said: “I’ll tell you, to the degree I can, when I get back what I talk about with him.”