The US has said a tape purported¹ to be from al-Qaeda leader Osama Bin² Laden³ simply repeats "hollow justifications⁴ for the mass slaughter⁵ of innocents".

美国政府称，谣传的基地组织首领奥萨马·本·拉登流传出的录音，只是简单地重复着“为大量屠杀无辜人员进行虚伪的辩护”。

White House adviser⁶ David Axelrod also said that the US could not confirm the authenticity真实性，确实性 of the audio tape.

The tape warned US President Barack Obama there would be more attacks if the US continued to support Israel.

In the tape aired by al-Jazeera, the speaker said US would not live in peace until there was "peace in Palestine".

The message also claimed that al-Qaeda was behind the 25 December attempt to blow up爆炸 a passenger plane bound for开往 the US.

A Nigerian man, Umar Farouk Abdulmutallab, has been charged with attempting to blow up the Delta⁸ Airlines plane as it approached Detroit from Amsterdam.

'No safe life'

Mr Axelrod told CNN the US could not immediately confirm the authenticity⁷ of the tape.

"But assuming that it is him [Bin Laden], his message contains the same hollow空的，虚伪的 justifications理由，辩护 for the mass slaughter of innocents that we've heard before," he said.

Israeli foreign ministry⁹ spokesman Andy David told Associated Press news agency: "This is nothing new; he has said this before. Terrorists always look for absurd excuses for their despicable卑劣的，可耻的 deeds."

And in London, UK Foreign Secretary David Miliband said he needed to study the message, but pointed¹⁰ to the importance of the Detroit plot as "an attack on the West rather than an attack within the Middle East".

However, the head of the United Nations al-Qaeda monitoring team later told the BBC he believed the tape was genuine.

Richard Barrett said that there were "other, previous tapes that it can be compared with and I think it's quite straightforward¹¹简单的，明确的 on basic voice analysis to decide whether it is indeed Osama Bin Laden".

"And I would imagine in this case that it will be."