Updated

On a new audiotape said to be from Usama bin Laden, a male voice warns that the "youths of God" are planning more attacks against the United States.

The Arab satellite station al-Jazeera, which broadcast the tape Sunday, said the voice was that of bin Laden, but there was no way to verify that claim or when the recording was made.

"By God, the youths of God are preparing for you things that would fill your hearts with terror and target your economic lifeline until you stop your oppression and aggression" against Muslims, the voice said.

U.S. officials have said they don't know whether bin Laden, whose Al Qaeda terror group is thought to have carried out the Sept. 11 terror attacks, is still alive. The U.S. State Department had no immediate reaction to the tape.

Al-Jazeera chief editor Ibrahim Helal told The Associated Press by telephone that the station received the tape two hours before the Sunday evening broadcast. He refused to say how the tape was received.

"We had no doubt this was bin Laden. It was not only the tone of the voice but also the way he spoke and the logic of the message," Helal said.

He said the fact the message was so brief "showed that the man [bin Laden] was in tough circumstances and does not have a chance to talk."

Qatar-based al-Jazeera has become known for its broadcast of audio and videotapes of Al Qaeda leaders. Last month, it aired excerpts from a videotape in which a voice said to be bin Laden's is heard naming the leaders of the 19 Sept. 11 hijackers.

Until then, bin Laden had not been heard from since shortly after the U.S.-led bombing campaign began in Afghanistan last October.

In the recording broadcast Sunday, the man said his message was addressed to the American people, whom he urged to "understand the message of the New York and Washington attacks which came in response to some of your previous crimes."

"Those who have initiated [the attacks] are the ones who brought injustice," he said.

"But those who follow the activities of the band of criminals in the White House, the Jewish agents, who are preparing for an attack on the Muslim world ... feel that you have not understood anything from the message of the two attacks," he said.

"So let America increase the pace of this conflict or decrease it, and we will respond in kind," he said.

The reference appeared to be to the U.S.-Iraq confrontation many believe will lead to war, which would date the tape to recent weeks. The reference, however, could have been to another conflict.

Al-Jazeera said one of its correspondents conducted an interview in June with two top Al Qaeda fugitives was aired to correspond with the first anniversary of the Sept. 11 attacks. Shortly afterward, U.S. officials announced one of the fugitives had been captured in Pakistan.