(CN) – President Donald Trump’s longtime attorney Michael Cohen plans to invoke his Fifth Amendment right against self-incrimination in the Stormy Daniels case, according to the adult film star’s attorney.

In a conversation with MSNBC host Nicole Wallace Thursday, Michael Avenatti said his legal team has learned Cohen plans to file for an emergency stay of the defamation charges filed against him by Daniels in an effort to delay proceedings.

Cohen will plead the Fifth Amendment if the motion is denied by U.S District Judge James Otero, Avenatti said.

Avenatti said on Twitter the news was a “a stunning development, the seriousness of which cannot be overstated.”

Federal agents carrying court-authorized search warrants seized documents from Cohen’s office, hotel and home on Monday.

His attorney Stephen Ryan said the search warrants were executed by the office of the U.S. Attorney for Southern District of New York. The referral for the raid came from special counsel Robert Mueller who is leading an ongoing investigation into Russian meddling in the 2016 election.

Trump called the seizure of Cohen’s documents “a disgrace” and ‘an attack on our country.”

Daniels will oppose the motion, Avenatti said, adding that they have “very good grounds as to why there should be no delay.”

Daniels, given name Stephanie Clifford, hit Cohen with defamation claims after he made public statements questioning whether her account of her affair with Trump could be trusted. Daniels said she had sex with Trump in 2006 and later tried to share her account with media publications.

The White House and Trump have denied the affair took place.

On Monday, Daniels renewed her motion to depose Trump and Cohen over details of a nondisclosure agreement she signed days before the 2016 presidential election. Daniels is asking the district court to find the agreement “void, invalid and unenforceable” because Trump never signed it.

Cohen paid Daniels $130,000 as part of the agreement, which he said came from his own funds.

Trump and Cohen have asked Otero to send the case to private arbitration, which Daniels has staunchly opposed.

As part of a motion to oppose the arbitration demand, Daniels filed a declaration in court this week, saying she wouldn’t have agreed to terms of the nondisclosure agreement on the affair if she knew Trump wasn’t a party to it.

By pleading the Fifth, Cohen signals he seeks to avoid self-incrimination by refusing to answer any further questions or produce statements about the case.

The move by Cohen is a response to the specter of facing at least two hours of questioning in a deposition, Avenatti said. If Otero grants the motion to depose, Trump would also face questioning under oath on his knowledge of the agreement with Daniels and subsequent payment by Cohen.

Trump made his first public remarks about the case on April 5, telling reporters aboard Air Force One he had no prior knowledge of the payment.

Trump has been outspoken in the past about the character of people who invoke their Fifth Amendment rights.

At a Sept. 2016 campaign rally in Iowa, Trump said “the mob” pleads the Fifth. “If you’re innocent, why are you taking the Fifth Amendment?”

Cohen and Avenatti did not return requests for comment by press time.

Avenatti has asked Otero that a hearing on the renewed motion to depose be scheduled for May 7.