WASHINGTON – Former Trump campaign chairman Paul Manafort lied repeatedly to the FBI, violating a plea agreement with Justice Department special counsel Robert Mueller, who recommended that Manafort receive no credit to reduce his prison sentence.

Manafort could face severe punishment for his conviction in August in an Alexandria federal court and for a separate guilty plea in the District of Columbia.

In the D.C. case, Manafort faces the prospect of perhaps a decade in prison, unless he is pardoned by President Donald Trump.

"The government will file a detailed sentencing submission ... that sets forth the nature of the defendant’s crimes and lies, including those after signing the plea agreement herein," prosecutors said in a brief court filing late Monday.

"As the defendant has breached the plea agreement, there is no reason to delay his sentencing," prosecutors said.

Manafort was convicted on eight counts of financial fraud in a trial in August during which the jury deadlocked on 10 other counts. Those undecided counts were dismissed.

Manafort's trial in Virginia was the first contested prosecution brought by Mueller.

After striking a deal to cooperate with Mueller's team in September, Manafort met with prosecutors, which authorities hoped would benefit the investigation into Russia's interference in the 2016 election.

Manafort was not convicted in either Virginia or the District of Columbia of participating in election interference. His oversight of the Trump campaign and his participation in key meetings, including a Trump Tower gathering in 2016 of top campaign advisers with a Russian attorney promising damaging information on Democratic presidential nominee Hillary Clinton, made him a potentially valuable witness as Mueller's team investigated whether the Trump campaign coordinated with Russia.

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"A breach (in the plea agreement) relieves the government of any obligations it has under the agreement, including its agreement to a reduction in the sentencing guidelines for acceptance of responsibility, but leaves intact all the obligations of the defendant as well as his guilty pleas," prosecutors said in court documents.

Manafort's legal team asserted that he lived up to his promise to cooperate with prosecutors during a series of meetings.

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"After signing the plea agreement, Manafort met with the government on numerous occasions and answered the government’s questions," defense attorneys contended in court documents. "Manafort has provided information to the government in an effort to live up to his cooperation obligations. He believes he has provided truthful information and does not agree with the government’s characterization or that he has breached the agreement."

Citing the government's conflicting position, defense attorneys agreed that there is "no reason to delay" sentencing in the D.C. case.

A separate sentencing has been set for Feb. 8 in the Virginia case.

Manafort's decision to cooperate in the related D.C. case raised expectations that Mueller's team would be carried further into Trump's inner circle by a once-trusted adviser who had deep access to the presidential candidate's political strategy.

Asked in September whether Manafort’s deal included an agreement to provide information related to Trump, defense attorney Richard Westling said his client pledged “complete cooperation.”