'Fire & Fury' Author Michael Wolff Claims Trump Is Having an Affair: 'Read Between the Lines'

Author Michael Wolff made several headline-making accusations about President Donald Trump in his bestselling bombshell book Fire and Fury: Inside the Trump White House. But now he’s claiming there’s one piece of gossip that wasn’t in his book — that Trump is currently having an affair.

“There is something in the book that I was absolutely sure of but it was so incendiary that I just didn’t have the ultimate proof,” Wolf explained on Friday’s Real Time with Bill Maher about Trump’s alleged indiscretion, later referencing the piece of evidence that exposed former President Bill Clinton’s affair with Monica Lewinsky in the ’90s. “I didn’t have the blue dress.”

Maher, 62, pressed for details, asking, “It’s somebody [Trump is] f—— now?”

“It is. And it’s… you just have to read between the lines,” Wolff said, adding that the White House has “back doors” that allow visitors to enter without being noticed. “It’s toward the end of the book. You just have to… you’ll know it. Now that I’ve told you, when you hit that paragraph, you’re going to say, ‘Bingo.’ ”

Warning: video above contains graphic language

White House representatives did not immediately respond to PEOPLE’s request for comment, but Trump, 71, has said on Twitter that Wolff’s book was “phony” and “full of lies, misrepresentation, and sources that don’t exist.”

Trump’s first marriage to Ivana, 68, broke up in the early 1990s after his highly publicized affair with then-model Marla Maples, 54. Trump was married to Maples from 1993-1999. He’s been married to former model Melania, 47, since 2005.

Wolff’s book details claims Trump and Melania spent relatively little time together during his presidential campaign, sometimes going days at a time without any contact at all even when they lived together in Trump Tower.

Their marriage was “perplexing” to almost everyone who worked closely with Trump during the campaign, says Wolff. But to Trump, this arrangement spelled success. The real estate mogul reportedly told friends he had finally perfected the art of marriage: “Do your own thing.”

On Saturday, Melania celebrated the one-year anniversary of the inauguration by sharing a photo of herself on that 2017 day without her husband. “This has been a year filled with many wonderful moments,” she wrote on Twitter. “I’ve enjoyed the people I’ve been lucky enough to meet throughout our great country & the world! 🇺🇸”

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Fire & Fury also describes Trump as a “world-class harasser,” noting that as his campaign went on, he faced growing allegations of molestation and harassment. More than a dozen women have accused Trump of sexual misconduct, including PEOPLE writer Natasha Stoynoff, who alleges Trump forcibly kissed her at Mar-a-Lago while a pregnant Melania was in another room. (Trump has repeatedly denied all claims of sexual misconduct.)

Wolff claims Trump is a “notorious womanizer” who’s often said that one of the things that makes life worthwhile is “getting your friends’ wives into bed.”

In pursuing a friend’s wife, Wolff alleges that the “scrupleless” Trump would try to show the woman in question that her husband was susceptible to straying. More than once, Trump reportedly invited a male friend to his office and then tried to entrap the friend into admitting he’d been unfaithful or would be unfaithful to his wife — all while the wife was on speakerphone, listening in.

“Do you still like having sex with your wife? How often? You must have had a better f— than your wife? Tell me about it,” Trump would allegedly say. “I have girls coming in from Los Angeles at three o’clock. We can go upstairs and have a great time.”

The federal government is currently in a partial shut down as Senate Democrats and Republicans debate the fate of young immigrants covered by the Deferred Action for Childhood Arrivals program.