(CNN) Former national security adviser Michael Flynn is ready to be sentenced, prosecutors and his defense team told a federal judge Monday. Flynn's sentencing had been delayed four times since he pleaded guilty to lying to investigators last December.

The change, indicated in a court filing, suggests that Flynn's cooperation with the Mueller investigation will end soon.

The legal teams have asked federal Judge Emmet Sullivan to set Flynn's sentencing for the end of November, well after the midterm elections.

Until three days ago, Flynn was the highest-ranking Trump associate cooperating with the probe into Russian interference in the 2016 presidential elections and its aftermath. On Friday, former Trump campaign chairman Paul Manafort pleaded guilty to two federal charges in DC District Court. He agreed to fully cooperate with Mueller as well.

Flynn cut a deal year, sidestepping additional, potentially more serious charges. Flynn admitted to lying about his communications with the Russian ambassador during Trump's presidential transition. He also said he had lied to the Justice Department in 2017 about doing consulting work for the Republic of Turkey, according to his court filings.

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