“Regarding the new policy of President Obama, we are studying that policy,” Mr. Gilani said. “We need more clarity on it, and when we get more clarity on it we can see what we can implement on that plan.”

He was also asked about Western demands that Pakistan hunt more rigorously for Mr. bin Laden, widely believed in Washington and London to have fled the Tora Bora region of Afghanistan after the fall of the Taliban regime there in late 2001.

“I doubt the information which you are giving is correct because I don’t think Osama bin Laden is in Pakistan,” Mr. Gilani said, echoing similar comments by other Pakistani leaders in recent years who have sometimes hinted that they believe Mr. bin Laden died of renal failure some time after trekking over the 14,000-foot shoulder of the Tora Bora mountains. The Pakistani leader did not indicate where Mr. bin Laden might be if he is not in Pakistan.

Western intelligence officials concluded long ago that the senior Qaeda leaders had taken sanctuary most likely in North or South Waziristan, some 200 miles from Islamabad, Pakistan’s capital.

Mr. Brown announced on Thursday that Britain would contribute around $83 million to help Pakistan pursue militants in the lawless regions along the Afghan border. His tone seemed milder than it had been over the weekend when, in two hard-edged statements, he signaled a renewed sense of impatience in the approach that Britain and the United States planned to take toward the governments in Kabul and Islamabad as the allies step up their commitment to the war against the Taliban and Al Qaeda.