The appeal coincided with Secretary of State Colin Powell's identifying Osama bin Laden as a key suspect in this week's terror attacks. Powell also was promised cooperation by Pakistan's president.

Bin Laden operates in Afghanistan with sanctuary provided by the Taliban, a fundamentalist Muslim group that controls most of the country.

The United States also asked Pakistan for permission to fly over its territory in the event of military action, said the White House official, who spoke on condition of anonymity.

Other nations will be asked to stop funding terrorist groups, the official said.

When the Bush administration is certain who sent suicidal hijackers on their mission, Powell said, ''We will go after that group, that network and those that have harbored, supported and aided that network, to rip that network up.''

He added, grimly: ''When we are through with that network, we will continue with a global assault against terrorism in general.''

At a news conference, Powell became the first senior administration official to say openly what many have been saying privately: that bin Laden is suspected of engineering the attacks.

''We are looking at those terrorist organizations who have the kind of capacity that would have been necessary to conduct the kind of attack that we saw,'' Powell said.

Close to 5,000 people are unaccounted for in the coordinated attacks that knocked down the Twin Towers of New York's World Trade Center and heavily damaged the Pentagon outside Washington. All three buildings were rammed by hijacked jetliners.

Powell noted that the administration was not on the record with the identity of the organization it believed responsible. ''When you look at the list of candidates, one resides in the region,'' he said.

Powell answered yes when asked whether he was referring to bin Laden, the Saudi-born exile who runs a terrorist network from Afghanistan.

After the news conference, Powell called President Pervez Musharraf of Pakistan, a neighbor of Afghanistan, to seek ''a specific list of things that we think would be useful for them to work on with us.''

They spoke for nearly 10 minutes. State Department spokesman Richard Boucher said they had a positive conversation and Powell received a commitment of cooperation.

Deputy Secretary of State Richard Armitage met separately with the Pakistani ambassador to Washington, Maleeha Lodhi, and the country's intelligence chief, Mahmoud Ahmed.

Armitage gave them a list of what the United States wants from Pakistan, which includes information on terror networks, and specified a number of areas where Pakistan can help, a senior U.S. official said.

In Islamabad, Musharraf pledged ''unstinted cooperation in the fight against terrorism.''

Powell's statements indicated the United States could strike Afghanistan if it concludes bin Laden was behind the attacks.

Iraq's role in helping the terror network also is under scrutiny, a U.S. official told The Associated Press.

Powell would not discuss a connection to Baghdad but spoke scornfully of President Saddam Hussein as ''one of the leading terrorists on the face of the Earth.''

Meanwhile, Armitage scheduled a trip to Moscow on Wednesday to discuss Afghanistan and follow up on a Russian offer to help in the investigation.

The Soviet Union fought a 10-year war with Muslim fundamentalists after invading Afghanistan and setting up a puppet government in 1979. The United States opposed the Soviet invasion and provided weapons to the insurgents through Pakistan.

The Central Asian countries that formed the underbelly of the Soviet Union have emerged as the battleground for an Islamic insurgency aided by Afghanistan that threatens to destabilize the region.