The top two U.S. intelligence officials made a secret visit to Pakistan in early January to seek permission from President Pervez Musharraf for greater involvement of American forces in trying to ferret out Al-Qaeda and other militant groups active in the tribal regions along the Afghanistan border, a senior U.S. official said.

The official, speaking on condition of anonymity given the secret nature of the talks, declined to disclose what was said, but Musharraf was quoted two days after the Jan. 9 meeting as saying U.S. troops would be regarded as invaders if they crossed into Pakistan to hunt Al-Qaeda militants.

The New York Times — which first reported on the secret visit by CIA Director Michael Hayden and Mike McConnell, director of national intelligence — said Musharraf rebuffed an expansion of an American presence in Pakistan at the meeting, either through overt CIA missions or by joint operations with Pakistani security forces.

Pakistan has been under growing U.S. pressure to crack down on militants in its tribal regions close to the Afghan border, a rugged area long considered a likely hiding place for Al-Qaeda leader Usama bin Laden and his top deputy, Ayman Al-Zawahri, as well as an operating ground for Taliban militants planning attacks on coalition forces in Afghanistan.

Several U.S. presidential candidates have hinted they would support unilateral action in the area.

In a Jan. 11 interview, Musharraf told The Straits Times of Singapore that U.S. troops would "certainly" be considered invaders if they set foot in the tribal regions. "If they come without our permission, that's against the sovereignty of Pakistan," he said. "I challenge anybody coming into our mountains. They would regret that day."

South Waziristan is a semiautonomous region where the central government has never had much control. It is home to scores of Al-Qaeda and Taliban fighters, many of whom fled there from neighboring Afghanistan after the U.S-led invasion in 2001.

The border region emerged as a front line in the war on extremist groups after Musharraf allied Pakistan with the U.S. following the Sept. 11 terror attacks. Washington has given Pakistan billions of dollars in aid to help government forces battle militants.

Musharraf, who toured Europe last week seeking support for his embattled government, rejected claims that the violence was a sign of a resurgent Taliban. More than 150 rebels and soldiers are reported to have been killed in the region this month alone.

Musharraf in the past has credited cooperation between Pakistani intelligence services and the CIA, both of whom believe that Pakistani militant leader Baitullah Mehsud was the mastermind of the Dec. 27 gun and suicide bomb attack that killed former prime minister Benazir Bhutto.

But the State Department's counterterrorism chief, Dell Dailey, said Tuesday that the Bush administration was displeased with "gaps in intelligence" received from Pakistan about the activities of extremist groups in the tribal regions.

"We don't have enough information about what's going on there. Not on Al-Qaeda. Not on foreign fighters. Not on the Taliban," he said.

Dailey, a retired Army lieutenant general with extensive background in special operations, said Pakistan needs to fix the problem. However, he said the U.S. was not likely to conduct military strikes inside Pakistan on its own, saying that would anger many Pakistanis.

Rather than allow an increased U.S. presence, the Times reported that Pakistan and the United States are discussing other joint efforts, such as increased use of armed Predator surveillance aircraft over the tribal areas, and identifying ways the U.S. can speed intelligence information to Pakistani security forces.

The paper said the Jan. 9 trip by McConnell and Hayden came five days after senior administration officials debated new strategies for dealing with Pakistan. It had reported previously that no decisions were made at that meeting of the National Security Council, which included top administration officials, but not President George W. Bush.

The times quoted a senior officials as saying "the purpose of the mission (by McConnell and Hayden) was to convince Musharraf that time is ticking away" and that the increased attacks on Pakistan would ultimately undermine his effort to stay in office.