- Karen McDougal says she had sexual relationship with Donald Trump in 2006
- She said relationship happened months after Trump's youngest son was born
- President Trump previously denied relationship, calling it "fake news"
Former Playboy model Karen McDougal claims that she and Mr Trump had a sexual relationship in 2006, months after first lady Melania Trump gave birth to the president's youngest son.
The White House did not immediately reply to a request for comment, but in a statement to NBC a spokesperson said the president had previously denied having a relationship with McDougal, calling the claims "fake news."
According to the New Yorker, the nine month relationship ended quietly, but years later - during the 2016 presidential campaign - Ms McDougal sold her story.
The New Yorker reported that on August 5, 2016, Ms McDougall agreed to give the company which owns the National Inquirer tabloid exclusive rights over "any romantic, personal, or physical relationship she has ever had with any 'then-married man.'"
The deal is alleged to have been worth $150,000, but the story never ran.
The National Enquirer is owned by David Pecker, who has claimed to be a friend of Trump's. The tabloid endorsed Trump's bid for the presidency.
"I'm the one who took it, so it's my fault, too. But I didn't understand the full parameters of it," Ms McDougal told the New Yorker of the alleged payment.
The model's story strongly echoes allegations of an affair between Trump and the porn star Stephanie Clifford - known as Stormy Daniels - during the same period.
In that case, the president's personal lawyer admitted to paying Ms Daniels $130,000 but refused to say why.
Good governance groups believe that could constitute a campaign donation and could breach election financial rules.
Get the latest election news, live updates and election schedule for Lok Sabha Elections 2019 on ndtv.com/elections. Like us on Facebook or follow us on Twitter and Instagram for updates from each of the 543 parliamentary seats for the 2019 Indian general elections.