Osama bin Laden claimed responsibility for the failed attempt to blow up a Detroit-bound airliner on Christmas Day in a new audio message released Sunday, in which the Al Qaeda leader also threatened more attacks against the United States.
However, experts say that there is little proof to support the claims.
In the minute-long message, which was broadcast by the Al-Jazeera news channel, bin Laden spoke directly to U.S. President Barack Obama.
"The message delivered to you through the plane of the heroic warrior Umar Farouk Abdulmutallab was a confirmation of the previous messages sent by the heroes of the Sept. 11," he said. "America will never dream of security unless we will have it in reality in Palestine," he added.
"God willing, our raids on you will continue as long as your support for the Israelis continues."
Abdulmutallab, a Nigerian national, was arrested Christmas Day after he attempted to use a homemade explosive that was hidden in his pants to blow up a Northwest Airlines flight as it was preparing to descend into the Detroit airport.
The incident delayed and cancelled thousands of flights around the world, and led airports to issue drastic new security measures, including the implementation of full-body scanners.
Abdulmutallab, 23, pleaded not guilty to six charges, including the attempted use of a weapon of mass destruction. He is currently being held in a Detroit jail.
When he was arrested, Abdulmutallab claimed he had been trained and provided with the explosives by al Qaeda in the Arabian Peninsula, an al Qaeda affiliate based in Yemen.
U.S. intelligence officials have linked the Yemen group to bin Laden's organization via communications between Yemen and Pakistan.
However, U.S. State Department spokesman P.J. Crowley said there is little to confirm bin Laden's claim of responsibility.
"He's trying to continue to appear relevant," Crowley said.
In fact, the al Qaeda leader had not been heard from since September, and he may be using the plot to solidify his reputation as the terror network's ideological head, experts agree.
There have also been indications that bin Laden's role in the network has shifted as al Qaeda has become decentralized in recent years.
"So, in many ways you can say bin Laden is exploiting for his benefit this particular attack. Bin Laden still wants to claim leadership for the global jihad movement," said author and terror expert Rohan Gunaratna.
Echoing that opinion, a senior U.S. intelligence official in Washington told The Associated Press there is "no evidence whatsoever" that bin Laden was involved in the attempted bombing on Christmas or knew about it beforehand.
The official, who spoke on condition of anonymity, said it appears bin Laden wants to give the appearance he is in direct control of al Qaeda and its affiliates around the world.
What is known is that the group in Yemen may be the closest of the al Qaeda affiliates to bin Laden, given that many of its top associates are his former bodyguards. Yemen is also bin Laden's ancestral homeland.
White House spokesperson Robert Gibbs told Fox News Sunday that "nobody's had a chance to authenticate that tape," and would not comment on whether U.S. officials believe bin Laden was the incident's mastermind.
"Everybody in this world understands that this is somebody that has to pop up in our lives over an audio tape because he's nothing but a cowardly murderous thug and terrorist that will some day -- hopefully soon -- be brought to justice," Gibbs said.
