It's a ninety-second message to the American people, according to ABC News.
Bin Laden says al Qaeda will execute any "American we have" if the US executes Khalid Sheik Mohammed.
No date reference in the audio, so it is not possible to tell when it was recorded.
He goes on to say "your friend in the White House" continues to go in the "wrong way."
A brief portion of the audio aired on Al Jazeera on March 25, 2010, so the recording is not entirely new.