Secretary of State Colin Powell says the United States intends to lead a global war on terrorist groups that will go beyond the promised U.S.-led assault against those found responsible for the New York and Washington attacks. He also confirms that Saudi exile Osama bin Laden and his organization is a key suspect.

Mr. Powell became the first senior administration official Thursday to publicly identify Osama bin Laden group's as a leading suspect in the U.S. attacks, replying in the affirmative when asked at a news conference if the Saudi exile and his followers were under scrutiny.

The Secretary of State said the administration has not made a final conclusion as to who is responsible, but said a focus on the Bin Laden group is "prudent" given, among other things, its known capabilities.

He said once the United States has assembled evidence the world will find convincing about who is to blame, it will undertake sweeping action. "At that point we will go after that group, that network and those who have harbored, supported and aided that network to rip the network up," Secretary Powell said. "And when we're through with that network, we will continue with a global assault against terrorism in general."

Mr. Powell spoke to reporters moments before a phone conversation with Pakistani President General Pervez Musharaff, whose government has close ties with the Taleban leaders in Afghanistan who have sheltered the Bin Laden group.

An official here said the Powell-Musharaff talk was positive and that the Pakistani leader repeated his commitment to work with the United States.

Mr. Powell said the administration has "specific list" of things it would like the Pakistani government to do, but declined to call them demands and stressed the United States "friendly" relationship with Pakistan.

The Secretary of State also said he was gratified by the pledges of support the United States has gotten as it seeks to build an international coalition against terrorism. But he also made clear that the administration will not feel constrained if it believes it must act unilaterally. "I think we all can agree that these kinds of organizations should be isolated, financially, legally in terms of getting into safe-haven countries," said Mr. Powell. "So there are many things we can do together. There may be some things the United States has to do alone and we will always reserve the right to do that."

The Secretary of State is sending his deputy, Richard Armitage, to Moscow next week for a meeting of a U.S.-Russian working group on Afghanistan.

Alluding to the Afghan war of the 1980's, Mr. Powell said Russians have a great deal of experience in Afghanistan which the United States intends to draw upon.