The sentencing of former D.C. Council chairman Kwame R. Brown, who pleaded guilty in June to bank fraud, has been postponed until November.

U.S. District Court Judge Richard J. Leon disclosed the decision Monday in a docket entry that rescheduled the sentencing from Sept. 20 until 11 a.m. Nov. 12. The judge, who based his decision on sealed court motions, cited the need to give Brown more time “to complete his cooperation.” Under terms of his plea deal, Brown agreed to cooperate with federal prosecutors and agents investigating his case.

The docket entry noted that Leon denied a motion to file court papers under seal but granted another to postpone the sentencing. It is not clear whether the motions were filed by the government or Brown’s lawyer, Frederick D. Cooke Jr.

A spokesman for the U.S. Attorney’s Office declined to comment. Cooke did not immediately reply to a phone message seeking his reaction to the order.

Brown resigned as Council chairman just two days before pleading guilty in early June to bank fraud and a separate misdemeanor charge of violating city campaign law. He admitted that he lied on bank loan applications and that his campaign paid an expense in cash that was greater than $50. Under federal guidelines, Brown faces up to six months in jail on the bank fraud charge. The misdemeanor is being heard in D.C. Superior Court.