Cairo, Egypt ? A man identified as Osama bin Laden, speaking on an audiotape posted on an Islamic Web site Thursday, praised the men who attacked a U.S. consulate in Saudi Arabia earlier this month and called on militants to stop the flow of oil to the West.

The voice sounded like the al-Qaida terror chief’s, and the tape, which was more than an hour, was posted on a site known as a clearinghouse for militant Islamic comment.

The tape appeared the same day another dissident had called for anti-monarchy protests in the kingdom.

In Washington, Secretary of State Colin Powell said U.S. intelligence officials were analyzing the tape, and “it appears to be” the voice of bin Laden.

When asked whether he thought bin Laden was trying to taunt the United States and Saudi Arabia, Powell replied, “He’s a terrorist. That’s what terrorists do. He’s a criminal, he’s a terrorist, he’s a murderer and we’re going to continue to hunt for him.”

The State Department said later Thursday that it did not have an official transcript of the tape, but “the intelligence community has assessed with high confidence that the voice is that of bin Laden.”

The speaker urged Islamic militants to stop Westerners from obtaining Middle Eastern oil, saying such a blow would be fatal to the West.

“Try your best to stop the biggest theft in history,” the speaker said, accusing the West of buying oil too cheaply.

“Go on and try to prevent them (Westerners) from getting oil,” the speaker told militants. “Concentrate your operations on that, especially in Iraq and the Gulf.”