Washington, Jun 13 (IANS): Melania Trump used her position as the US First Lady to renegotiate her pre-nuptial agreement with husband, President Donald Trump before she moved into the White House after he was elected to office, a new book has revealed.

"The Art of Her Deal: The Untold Story of Melania Trump" by Washington Post reporter Mary Jordan, "draws an unprecedented portrait of the First Lady" based on interviews with more than 100 people in five countries, the Daily Mail said in a report on Friday.

Released on Tuesday, excerpts from the 286-page book appeared in The Washington Post on Friday, confirming a long-time rumour that Melania Trump had renegotiated her marital agreement with her husband.

Melania didn't move into 1600 Pennsylvania Avenue until June 2017 - six months after the President took the oath of office. And she used that time to renegotiate her prenuptial agreement, claimed the book.

Jordan's book notes that Melania Trump did want the couple's son Barron to finish out his school year in New York but she also need time to "cool off" after learning details about Trump's marital infidelities, news she learned from media accounts, which included his affair with Playboy Playmate Karen McDougal and his "grab them by the p****" comment on the 'Access Hollywood' tape.

But Trump's victory in the 2016 election meant he needed a First Lady by his side and she used her new-found leverage "to amend her financial arrangement with Trump - what Melania referred to as 'taking care of Barron'".

"She wanted proof in writing that when it came to financial opportunities and inheritance, Barron would be treated as more of an equal to Trump's oldest three children," the Daily Mail cited an excerpt from the book as saying.

But the Melania Trump's office blasted the book as "fiction".

"Yet another book about Mrs. Trump with false information and sources. This book belongs in the fiction genre," Stephanie Grisham, the First Lady's Chief of Staff, said in a statement to the Daily Mail on Friday.