Stormy Daniels is interviewed by Anderson Cooper of CBS News' 60 Minutes program. Picture: Reuters

Washington - President Donald Trump's personal lawyer, Michael Cohen, demanded Stormy Daniels "cease and desist" after the adult-film star said in a "60 Minutes" TV interview that she was threatened with violence to stay silent about an alleged affair with Trump.

"Mr. Cohen had absolutely nothing whatsoever to do with any such person or incident, and does not even believe that any such person exists, or that such incident ever occurred," said the letter sent by Cohen's attorney, Brent Blakely, to the lawyer representing Daniels, Michael Avenatti, late on Sunday, shortly after the interview aired on CBS. A copy of the letter was viewed by Reuters on Monday.

Daniels, whose real name is Stephanie Clifford, had implied Cohen was behind the threat of harm if she did not "leave Trump alone," which was made by a stranger in a Las Vegas parking lot in 2011.

The letter also demanded "that you immediately retract and apologize to Mr. Cohen through the national media for your defamatory statements on '60 Minutes,' and make clear that you have no facts or evidence whatsoever to support your allegations that my client had anything whatsoever to do with this alleged thug."

Daniels sued Trump on March 6, saying he never signed an agreement for her to keep quiet about an "intimate" relationship between them in 2006.

White House aides did not respond immediately to requests for comment after the interview aired.

Daniels attorney Avenatti on Monday morning spoke with major news broadcasts.

Stormy Daniels is interviewed by Anderson Cooper on 60 Minutes. Picture: Reuters

In an interview with NBC, he said the man who threatened Daniels while she was with her infant daughter was not Cohen but that "it had to be someone that is related to Mr. Trump or Mr. Cohen."

Asked about the cease-and-desist letter on CNN, Avenatti said Cohen "needs to stop hiding behind pieces of paper and come clean with the American public."

Daniels' appearance followed an interview aired last week on CNN with former Playboy model Karen McDougal, who described a 10-month-long affair with Trump starting in 2006. Trump would have been married to his wife, Melania, during both alleged relationships.

The White House and Cohen have both denied Trump had an affair with Daniels. The White House has said Trump denies having an affair with McDougal.

Cohen said he paid Daniels $130,000 of his own money during the 2016 presidential campaign, but has not explained why or if Trump was aware of the payment. In filings with the Justice Department and Federal Election Commission watchdog groups have said the payment amount may have exceeded campaign-contribution limits and violated U.S. law.