They told U.S. District Judge Marcia Cooke the delay was needed so they could give another 4,700 classified military documents to Padilla's attorney, the South Florida Sun Sentinel reported Wednesday.
Padilla, 43, was sentenced to 17 years in prison in 2007 after being convicted of terrorism support and conspiracy charges. A federal court ruled in 2011 that Cooke was wrong in giving him less than the 30-year prison term he was facing because she discounted his previous conviction for murder and his 17 arrests.
The Chicago gang member converted to Islam in Florida while serving time in the Broward County jail. He underwent terrorism training with al-Qaida before the Sept. 11, 2001, attacks.
When initially arrested in 2002, he was charged with planning to set off a radioactive "dirty bomb" in the United States. That charge was later dropped.
During the Wednesday hearing, prosecutors said they had already given the defense more than 6,000 pages of classified documents and 2,500 unclassified documents.
Padilla's resentencing has been delayed several times since being moved to the federal detention center in Miami in 2012 from the federal "Supermax" prison in Colorado.