WASHINGTON — When Pakistan’s president arrives here on Friday, he will be grilled about his decision this month to release more than 1,000 prisoners, some of whom are suspected to be high-value Al Qaeda operatives.

The problem for the White House is that America does not know which prisoners were released as part of a ceasefire agreement the Pakistani military signed with tribal leaders in the border province of Waziristan. Pakistani officials have yet to share the names with their American counterparts, according to an intelligence official and an administration official who spoke on condition of anonymity.

The officials said one of the White House’s top goals for the meeting between President Musharraf and President Bush is to persuade the Pakistani leader to give up the dossier on the prisoners. While Bush administration officials have publicly praised the agreement — whereby 80,000 Pakistani soldiers will remain in Waziristan but will not conduct house-to-house raids or other intrusive patrols — privately it is viewed with more suspicion. In the last week, scant details of those released from the Pakistani prisons have surfaced in the local press in Waziristan, as well as in the London DailyTelegraph.

Pakistani officials have downplayed the prisoner release. In a story on the UPI news wire this week, a spokesman for Mr. Musharraf said that only a few dozen local fighters were released.

But Langley and the Pentagon do not share this view, the intelligence official told The New York Sun yesterday. “Frankly, we are very worried about this,” he said. “We can’t get straight answers on who was released.”

The administration official said, “We know they are releasing some individuals. The $64,000 question is: Who are they?”

Two names that have surfaced in the Pakistani press are Ghulam Mustapha, a man American intelligence considers to be a top fixer for Pakistan’s jihadist community, and Fazl Raziq, a Pakistani national thought to be a top aide to Osama bin Laden. Many analysts here believe Mr. bin Laden is hiding in Waziristan.

One concern for the intelligence community is whether Omar Sayed Sheikh was among the released prisoners. “I have been asking about this for a week now,” the intelligence official said of Mr. Sheikh, who is one of the men alleged to have killed a Wall Street Journal reporter, Daniel Pearl, in 2002. “I am not getting any straight answers.

The atmosphere surrounding Mr. Musharraf’s visit is already strained. On Wednesday, Mr. Bush told CNN that he would send American troops to Pakistan if he thought he could capture Mr. bin Laden. Mr. Musharraf countered yesterday that his country would never accept foreign soldiers on its soil. That point was underscored when the body of an Afghan national, Wazir Khan, was found in the main town of Waziristan, Mirin Shah, yesterday with a note attached that read in part: “See the body of this man who was spying for America. Anyone doing such a thing will face the same fate,” according to the Associated Press.

Despite the tension leading up to the meeting, the White House yesterday played up the get-together as a routine parley between two allies in the war on terror. A White House spokeswoman, Dana Perino, told reporters: “As we’ve said before, Pakistan is an important partner in the war on terror and a friend to the United States.We’ve had excellent cooperation in many areas, including counterterrorism. And the president has repeatedly said how much he appreciates Musharraf’s commitment to pursuing Al Qaeda and continuing to work with us in cooperation in the search for Osama bin Laden. Pakistan and the United States remain close allies, working not only on the war on terror together, but on many other areas.”

An analyst at the Middle East Institute, Syed Hasnat, said Mr. Musharraf had to sign the deal with the Waziri tribal leaders because the military occupation was not working.

“The Pakistani government asked the tribal leaders to hand over Al Qaeda to them. Many of them though had nothing to do with insurgency. This agreement was signed for peace and tranquility,” he said. “The Pakistani army failed to take control of the region militarily.”

Mr. Musharraf will be in America until next week. He is scheduled to meet with Mr. Bush and President Karzai of Afghanistan on Tuesday.