The White House has denied allegations that Donald Trump had an affair with an adult-film actress.
Stormy Daniels gave details about the alleged 2006 affair during an interview on CBS News’ 60 Minutes programme.
“The president doesn’t believe that any of the claims that Ms Daniels made last night in her interview were accurate,” said spokesman Raj Shah.
President Trump’s lawyers are seeking $20m (£14m) in damages from her, saying she broke a non-disclosure deal.
Ms Daniels, 39, told CBS in an interview aired on Sunday night that she had accepted $130,000 in “hush money” from Mr Trump’s lawyer, Michael Cohen, just before the 2016 election.
Ms Daniels is suing the president, alleging that the non-disclosure she signed is invalid because Mr Trump did not sign it.
On Monday, she amended her lawsuit to include Mr Cohen as a defendant, claiming he defamed her with a statement he made about the payment.
“Just because something isn’t true doesn’t mean that it can’t cause you harm or damage,” Mr Cohen said in a mid-February statement. “I will always protect Mr Trump.”
The amended lawsuit also claims the payment violated campaign-finance laws.
She said she originally accepted the “hush money” and signed the deal because she was concerned for the safety of her family.
Ms Daniels claimed in the Sunday night interview she was threatened by a stranger in a car park in 2011 to “leave Trump alone”.
But Mr Shah said the president does not believe Ms Daniels’ claim to be true, adding that Mr Cohen would need to be asked about the specifics of their monetary arrangement.
“The president strongly, clearly and consistently has denied these underlying claims, and the only person who has been inconsistent is the one making the claims,” said Mr Shah.
Mr Cohen’s lawyer sent a cease-and-desist letter to Ms Daniels following the interview, dismissing her claims about being threatened by a stranger.
“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 a letter by Mr Cohen’s attorney, Brent Blakely.
The letter also said Ms Daniels needed to immediately “retract and apologise 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”.
Mr Trump – who has no public events scheduled for Monday – did not comment himself about Ms Daniels’ story.
But he did tweet earlier: “So much Fake News. Never been more voluminous or more inaccurate. But through it all, our country is doing great!”
Mr Shah said Ms Daniels’ had been “inconsistent” in her claims about the sexual encounter.
“My understanding is that she signed the statements that conflict with what she said last night,” he said, refuting Ms Daniels’ claim that she felt pressured to sign the nondisclosure agreement despite her objections.
Ms Daniels is one of three women who have taken legal action that could damage Mr Trump.
Karen McDougal, a former Playboy model who claims she had an affair with Mr Trump between 2006 and 2007, has filed a lawsuit to invalidate a confidentiality agreement with tabloid newspaper the National Enquirer.
Stormy Daniels, whose real name is Stephanie Clifford, said she had consensual unprotected sex with Mr Trump once, in a hotel room during a celebrity golf tournament in Lake Tahoe, California, in July 2006. Mr Trump married Melania Trump in 2005.
And Summer Zervos, a former contestant on The Apprentice, accuses Mr Trump of sexually assaulting her at a Beverly Hills hotel in 2007.
Mrs Trump – who has not publicly responded to the claims made in Ms Daniels’ interview – did not return to the White House with her husband on Sunday from Florida.
The US first lady is said to be staying at Mar-a-Lago estate for spring holiday.
Spokeswoman Stephanie Grisham said Mrs Trump was “focused on being a mom and is quite enjoying spring break at Mar-a-Lago while working on future projects”.
Ms Daniels has meanwhile been capitalising on the purported scandal.
The 60 minutes interview- with 22.1m viewers- was its highest viewed episode in 10 years, according to CBS.
She has reportedly extended her nationwide tour of strip clubs, Making America Horny Again, until November.
Ms Daniels has also been touting a $14.99-per-month subscription to her naked web cam service.