(CNN) Federal prosecutors want to use Michael Flynn's former defense lawyers against him as they resist his attempts to get out of his guilty plea for lying to the FBI in 2017.

The court filing from prosecutors on Sunday could bring a new and consequential twist in the Flynn case, aligning the Justice Department and a major force in DC's legal establishment against President Donald Trump's first national security adviser. The filings even hint that DOJ would be willing to charge Flynn with perjury, or to take Flynn to trial if the judge allowed him to change his plea to not guilty.

The latest tussle in the case prompted District Judge Emmet Sullivan on Monday to cancel the date Flynn was scheduled to be sentenced, dragging a relatively straightforward plea deal case on indefinitely. Flynn's sentencing was initially set for February 27, but Sullivan now plans to allow at least two more weeks to weigh arguments and for Flynn's new lawyers and prosecutors to negotiate over the use of the former defense team's information in future proceedings.

Flynn was charged in December 2018 and was originally set to be sentenced last December, until he asked for a delay during the sentencing hearing.

In his guilty plea deal, Flynn admitted to lying to FBI agents interviewing him in the White House about his late-2016 conversations with the then-Russian ambassador. The episode ultimately led to his departure from the Trump administration, a series of events where special counsel Robert Mueller investigated Trump for obstruction of justice, and Flynn sharing extensive information about the President and his 2016 campaign with Mueller.

Flynn has claimed his former attorneys, from the law firm Covington & Burling, withheld information from him and pressured him into taking a plea deal during the Mueller's investigation. Flynn now claims he is innocent of lying to investigators, a crime to which he pleaded guilty two years ago.

But the prosecutors, from the DC US Attorney's Office, asked Sullivan on Sunday to give Covington permission to counter Flynn's claims, according to a new court filing. If allowed, the defense lawyers could even be called to testify against Flynn in future court proceedings, the prosecutors noted.

Flynn's recent moves to unravel his plea "put the representation of his former attorneys directly at issue," prosecutors wrote in a filing Sunday. "To make certain and clear that counsel may take the necessary steps to vindicate their public reputation by addressing and defending against the defendant's claims of ineffective assistance of counsel, and equally to vindicate the integrity of this Court's previous proceedings, the government asks this Court to" allow Covington to discuss its representation of Flynn with the prosecutors, the court and potentially in a public hearing.

Prosecutors wrote in a second court filing on Sunday they believe Covington would be willing to share information about Flynn if the judge orders that they can.

Covington declined to comment on the latest court filings Sunday.

Previously, following Flynn's accusations against his former attorneys, a spokesman for Covington told CNN, "Under bar rules, we are limited in our ability to respond publicly even to allegations of this nature, absent the client's consent or a court order."

Flynn has so far won delays for his sentencing several times by telling new stories to the court. Some have been unproven conspiracy theories that the Justice Department and judge later shot down. His recent requests pit Flynn's recounting of what happened during his plea negotiations against the silence of his former defense law firm, which is ethically bound not to betray confidential legal discussions with clients.

The prosecutors on Sunday also raised the possibility of charging Flynn with perjury. (Flynn under oath has said he is both guilty and not guilty, though he has not been charged with a perjury crime.)

If Sullivan were to let Flynn withdraw his guilty plea and contest his charge at a trial, it's possible the prosecutors wouldn't get wholesale access to whatever information Covington has on its representation of Flynn.

But any limits the judge may place on attorney-client discussions between Covington and Flynn "should not, however, preclude the government from prosecuting the defendant for perjury if any information that he provided to counsel were proof of perjury in this proceeding," the prosecutors wrote on Sunday.

Covington is one of the largest white-shoe law firms in Washington, DC.

After dumping his defense team from the firm last summer, Flynn hired a group of attorneys led by the Texas-based lawyer and right-wing TV commentator Sidney Powell.

Flynn's current lawyers have asked both the Justice Department and the judge to allow him withdraw his guilty plea. The DOJ appears unwilling to do that, and Sullivan hasn't yet ruled on his request.

Flynn hopes to avoid prison. He faces a likely sentence between zero to six months in prison, though Sullivan has wide ability to sentence Flynn as he sees fit, up to five years maximum in prison.

This story has been updated to reflect an indefinite delay in Flynn's sentencing.