"Last year, we frequently heard Arabs on radios talking about their hatred for (Afghan President Hamid) Karzai and Musharraf for supporting Americans, and we were able to trace al-Qaida hideouts in South Waziristan," said the official, who spoke on condition of anonymity. "Lately, such conversations have decreased."

Pakistan's optimism seems to be backed by senior U.S. military officials in the region.

Maj. Gen. Eric Olson, the No. 2 American commander in Afghanistan, said he had seen nothing to indicate that al-Qaida was attempting to get its hands on nuclear or biological weapons.

There is "no evidence that they're trying to acquire a terrorist weapon of that type and, frankly, I don't believe that they are regrouping," he told AP in a Feb. 25 interview.

"I think the pressure on them here, the pressure on them in Pakistan, the pressure on them in Iraq, is pretty great and it makes very difficult for them to operate," Olson added.

The skeptical assessments from officials here fly in the face of warnings out of Washington, where President Bush is pushing Congress to approve a $419 billion defense budget for 2006.

The Homeland Security Department late last month issued a classified bulletin to officials that bin Laden was enlisting his top operative in Iraq, Abu Musab al-Zarqawi, to plan potential attacks on the United States.

There have also long been fears — though no evidence to date — that rogue Pakistani nuclear scientists might have provided bin Laden's men with the know-how to build a crude atomic device or dirty bomb.

Newly installed CIA director Porter Goss and other senior American intelligence and military officials warned last month that terrorists are preparing for new strikes.

"It may be only a matter of time before al-Qaida or other groups attempt to use chemical, biological, radiological or nuclear weapons," Goss said at the Senate Intelligence Committee's annual hearing on threats, urging approval of the defense budget.

But Sherpao scoffed at such warnings.

"That is simply out of the question," he said of al-Qaida's ability to acquire weapons of mass destruction, adding that any al-Qaida leader who has escaped arrest was "more worried about their own safety."

"How can such people launch attacks with nuclear or chemical weapons?" he asked.

Maj. Gen. Olson, who leaves Afghanistan next month to return to the 25th Infantry Division back in Hawaii, said al-Qaida leaders were unable to use modern communications for fear of detection and were reduced to "16th century" techniques such as couriers. He said he wasn't discouraged by the success bin Laden and his deputy have had in releasing audio and videotapes filled with threats during the past few months.

"They can deliver all the videotapes they want, as long as they're not delivering weapons that can kill large numbers of people and I am convinced that their ability to coordinate large attacks like that is severely disrupted right now because of the pressure we have on them," he said.