Then-national security adviser Michael Flynn arrives before Canadian Prime Minister Justin Trudeau and President Trump hold a news conference at the White House on Feb. 13, 2017. (Carlos Barria/Reuters)

A federal judge set sentencing for Dec. 18 for Michael T. Flynn, President Trump’s former national security adviser, who admitted lying to the FBI about contacts with then-Russian Ambassador Sergey Kislyak in special counsel Robert S. Mueller III’s probe.

U.S. District Judge Emmet G. Sullivan of the District set the date in a court order Wednesday after prosecutors and attorneys for Flynn, in a joint filing Monday, requested sentencing between Nov. 28 and Dec. 7.

Sullivan directed prosecutors to file their recommended sentence by Dec. 4, Flynn’s attorneys by Dec. 11, and gave prosecutors three days after that to answer the defense proposal.

The sentencing date falls seven weeks after the Nov. 6 midterm congressional elections. The date could mark an end to the special counsel office’s investigation of matters related to the retired U.S. Army lieutenant general, or its need for his cooperation, and might serve as a deadline for the filing of any related charges or report. Prosecutors could still ask to push back the date, however.

Flynn pleaded guilty Dec. 1, becoming one of the first Trump associates to cooperate and the highest-ranking official charged in Mueller’s investigation of Russian interference in the 2016 presidential election.

He resigned from his top White House post in February 2017 after the White House said he misled Vice President Pence and other administration officials about his contacts with Kislyak.

Flynn’s plea revealed that he was in touch with senior Trump transition officials before and after his communications with the Russian ambassador. The pre-inauguration communications with Kislyak involved efforts to blunt Obama administration sanctions on Russia and a United Nations resolution on Israel.