Osama bin Laden has warned Barack Obama, the US president, that there will be further attacks on the United States unless he takes steps to resolve the Palestinian situation.
In an audio tape obtained by Al Jazeera on Sunday, the al-Qaeda chief, praised the Nigerian accused of a failed attempt to blow up an airliner heading for Detroit on Christmas Day.
"The message I want to convey to you through the plane of the hero Umar Farouk [Abdulmutallab], reaffirms a previous message that the heroes of 9/11 conveyed to you," Bin Laden said.
"America will never dream of living in peace unless we live it in Palestine. It is unfair that you enjoy a safe life while our brothers in Gaza suffer greatly.
"Therefore, with God's will, our attacks on you will continue as long as you continue to support Israel," bin Laden said.
"If it was possible to carry our messages to you by words we wouldn't have carried them to you by planes."
'Same hollow justifications'
"Therefore, with God's will, our attacks on you will continue as long as you continue to support Israel"
Speaker said to be Osama bin Laden
The Obama administration said intelligence analysts had not confirmed that the al-Qaeda leader's voice was on the tape.
But it quickly dismissed its significance.
David Axelrod, a senior Obama adviser, told CNN's State of the Union programme that "assuming that it is him, his message contains the same hollow justifications for the mass slaughters of innocents that we've heard before".
"And the irony is that he's killed more Muslims than people from any other religion - he's a murderer," Axelrod added.
Phil Rees, the author of Dining with Terrorists, told Al Jazeera: "Bin Laden has a great sense of timing; it's a complete poke in the eye to President Obama at a time when Obama is domestically suffering.
"The reference to Palestine is possibly the most interesting part of this because he almost now becomes the al-Qaeda leader that speaks about Palestine.
"The irony is that he's killed more Muslims than people from any other religion - he's a murderer"
senior Obama adviser
"What you've now got in Gaza is bin Laden looking at the situation where there's a peace process which is going nowhere, and in an ironic way, Hamas is at the frontline of the battle with al-Qaeda there."
Azzam Tamimi, a political analyst and the author of Hamas the Unwritten Chapters
, said that bin Laden was simply using the Palestinian issue in an attempt to mobilise Muslims against the US.
"I would say that al-Qaeda has not been able to set foot in many places in the Muslim world despite its rhetoric," he told Al Jazeera.
"In Palestine they failed miserably and that is why I understand this message as a return to the older strategy of waging war against America and the world order in the skies.
"It is very difficult to compete with an organisation like Hamas in Palestine."
Osama Hamdan, a spokesman for the Hamas movement, told Al Jazeera that the Palestinians were focused on ending the Israeli occupation.
"All Arabs and Muslims support our cause. [But] the Palestinian position is clear, the resistance is against the occupation, the Israeli army who is occupying and killing our people," he said.
"Everyone knows that the policies of the US have created huge problems in the region. At this moment, we know who our enemy is - the Israeli occupation."
'Subjected to scrutiny'
Imtiaz Gul, the chairman of the Centre for Research and Security Studies in Islamabad, questioned whether the tape was genuine.
|Bin Laden called bomb plot suspect Umar Farouk Abdulmutallab a 'hero' [EPA]
"I think the validity of this tape should be subjected to scrutiny because we haven't heard from Mr Bin Laden for quite some time."
The audio tape is believed to have been recorded last month.
In the attempted attack on Christmas Day, Abdulmutallab, who is now in US police custody, allegedly tried to ignite explosives sewn into his underwear as Northwest Airlines Flight 253 made its final descent to Detroit.
He had boarded the flight in Amsterdam, but purchased his tickets in Ghana on December 16.
Passengers on the flight were able to overpower the would-be bomber as he attempted to ignite the explosive's fuse.
After being taken into custody, Abdulmutallab told police he had been directed by al-Qaeda and had obtained his explosive device in Yemen.
Al-Qaeda in the Arabian Peninsula, the organisation's affiliate in Yemen, has said it armed Abdulmutallab, describing the attempted attack as revenge for the US role in a Yemeni military offensive against al-Qaeda.
Obama has criticised his own intelligence agencies for failing to piece together information about the suspect which should have stopped him boarding the flight.