When seeking the 45-day delay Tuesday, the lawyers said their case hinged on testimony that Mohammed, who has said he masterminded the 2001 terror attacks on the United States, is expected to give from his Guantanamo Bay, Cuba, prison cell, the Los Angeles Times reported.
Charges against Abu Ghaith, a son-in-law of al-Qaida founder Osama bin Laden (who was killed in 2011), include conspiring to kill Americans, providing material support to terrorists and threatening more plane attacks after Sept. 11, 2001.
In court documents, New York attorney Stanley Cohen said Mohammed would receive written questions Friday and needed at least four days to review them and respond. The timeline, he said, would make it impossible for Abu Ghaith's trial to begin Monday as scheduled.
"Mr. Mohammed's potential testimony is rendered all the more crucial in light of the changed circumstances," Cohen told the court, speaking of a decision by another Guantanamo Bay inmate, Salim Hamdan, a Yemeni who was bin Laden's chauffeur, not to assist in the case.
Abu Ghaith, a 48-year-old Kuwaiti, is allegedly a key al-Qaida propagandist.
The judge did not rule Tuesday on the delay request, the Times said.
Cohen also outlined details about a compromise reached last week with federal prosecutors for access to Mohammed and the handling of his responses.
"All of these questions and materials have already been approved for presentation to Mr. Mohammed," Cohen said, "with no challenge from the government as to their materiality or relevance to the defense of Abu Ghaith."