Tuesday's request for a sentencing delay indicates 'there's likely to be a big indictment in which Flynn is going to be one of the star witnesses,' said former Watergate prosecutor Nick Ackerman.

The move to delay sentencing for Trump’s former national security adviser Mike Flynn is “not good news for Donald Trump,” according to former assistant special Watergate prosecutor Nick Ackerman.

Commenting on a court filing submitted Tuesday seeking to delay Flynn’s sentencing by at least two months, Ackerman said the news is an ominous sign for Trump, because it indicates that Flynn is still talking — and special counsel Robert Mueller is still listening.

The request to push back sentencing for Flynn, who pleaded guilty to lying to the FBI, was submitted by Mueller’s office and attorneys for Flynn. They said Flynn is not ready for sentencing “due to the status of the special counsel’s investigation,” according to the federal court filing.

“This is not good news for Donald Trump,” Ackerman told MSNBC’s Ari Melber. “What they are looking to do is bring a major indictment in which Flynn is going to be one of the star witnesses. What Flynn wants to do is get as many brownie points as he can so when he goes to a sentencing judge he can say that he went all out, he testified for the government, he testified truthfully and as a result of his testimony there were a number of convictions.”

Ackerman also noted that Mueller likely “wants to kind of keep the lid on Flynn so that he has an incentive to go in and testify fully and truthfully. And by doing that, he keeps open sentencing.”

“Both sides have a big incentive to keep this [sentencing] open,” Ackerman added, “and it’s all open because there’s likely to be a big indictment in which Flynn is going to be one of the star witnesses.”

Flynn pleaded guilty in December to lying to the FBI about his contacts with Russian officials. As part of his plea deal, Flynn agreed to cooperate with Mueller’s ongoing investigation into Russian interference and potential coordination with the Trump campaign.

Tuesday’s request for a sentencing delay not only suggests that Flynn is still providing valuable information to Mueller, but that the investigation is not going to be wrapping up anytime soon.

That news is likely to come as a surprise to Rudy Giuliani, who joined Trump’s legal team six days ago with the promise that he would soon bring the Mueller probe to a close. Instead, the investigation looks to be entering an entirely new phase — and the implications look ominous for the man in the Oval Office.