The recording, posted on an Islamic website, has not been verified.

In the message a speaker identified as Bin Laden added fuel to the ongoing insurgency with a call for his Islamist fighters to focus their attacks on oil facilities in Iraq and the Gulf.

“Targeting America in Iraq in terms of economy and loss of life is a golden and unique opportunity… Be active and prevent them from reaching the oil, and mount your operations accordingly, particularly in Iraq and the Gulf,” he said.

In referring to the December 6 attack in which five militants shot their way into the compound of the US Consulate in Jeddah, Saudi Arabia, killing five non-American employees, the speaker said: “God bless our brothers who stormed the American consulate in Jeddah. Those who were killed of our brothers, we ask God to accept them as martyrs.”

Four of the attackers were killed and one was wounded in the consulate attack.

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

Asked if bin Laden was taunting the United States, Mr Powell said: “He’s a terrorist. That’s what terrorists do.”

“We’re going to continue to hunt for him …. He will be brought to justice,” Mr Powell added.

On the tape attributed to bin Laden, the speaker called for change in Saudi Arabia and derided overtures such as promised municipal elections and national dialogue Saudi rulers recently initiated to open public debate on democratisation and other issues.

“This hasn’t changed anything … the best they can do is that they will go into the elections game as happened before in Yemen and Jordan or Egypt and move in a vicious circle for dozens of years, this is regardless of the fact that it is prohibited to enter the infidel legislative councils,” the speaker said.

Addressing Saudi rulers, the speaker said: “You must know that people are fed up … security will not be able to stop them.”

He accused all Arab leaders of being puppets of the United States, singling out, in addition to Saudi rulers, interim Iraqi Prime Minister Iyad Allawi.

The speaker, in calm and even tones, accused Saudi rulers of “violating God’s rules,” a common theme of bin Laden, who accuses Saudi rulers of being insufficiently Islamic and too close to the “infidel” United States.

“The sins the regime committed are great … it practised injustices against the people, violating their rights, humiliating their pride,” the speaker said.

He accused the Saudi royal family of misspending public money while “millions of people are suffering from poverty and deprivation.”

The main statement was preceded by Koranic verses, a rhetorical device typical of bin Laden.

Saudi Arabia cracked down on Muslim extremists after the May 2003 bombings of three residential compounds in Riyadh brought terrorism home to the kingdom, but has not been able to stamp out the violence.

Bin Laden, believed hiding in the mountains along the Pakistan-Afghanistan border, last reached out to his followers in October, with a videotape aired on the Arabic TV station al-Jazeera.

In that statement, he for the first time clearly took responsibility for the September 11 attacks on the United States and said America could avoid another such strike if it stopped threatening the security of Muslims.