A federal judge denied Friday the defense's request to delay the trial of a man charged with attempting to blow up an airliner with explosives hidden in his shoe.

Richard Reid's lawyers requested that the start of his trial be postponed from Nov. 4 until early next year because they need more time to obtain security clearance for an expert they plan to call to the stand.

Owen Walker, one of Reid's public defenders, said the defense wants the expert to testify about classified documents prosecutors plan to submit during trial.

Reid, 29, a British citizen, is charged with attempting to detonate the explosives aboard an American Airlines flight from Paris to Miami on Dec. 22. Crew members and passengers subdued Reid, and the flight was diverted to Boston.

Prosecutors have said Reid was trained in Afghanistan by the Al Qaeda terrorist network.

U.S. District Judge William Young rejected the request to delay the trial, but ordered prosecutors to try to speed up government clearance of the defense witness.