WASHINGTON — First lady Jill Biden says she’s in a “work marriage” with her senior adviser Anthony Bernal, who can “make life hell” for White House staff with his “overbearing” persona, a new book reveals.

The 72-year-old first lady, who regularly travels on behalf of her 81-year-old husband, relies heavily on Bernal, New York Times reporter Katie Rogers writes in “American Woman: The Transformation of the Modern First Lady, from Hillary Clinton to Jill Biden.”

“Jill and Bernal are, as Jill puts it, in a ‘work marriage,’ but his reach extends beyond the East Wing,” according to the book, which hits shelves Tuesday.

Joe Biden and his wife Jill Biden kiss after he was sworn in as the 46th President of the United States on the West Front of the U.S. Capitol in Washington, U.S., January 20, 2021. REUTERS/Kevin Lamarque
President Biden, 81, has never been shy about his public displays of affection toward his wife Jill — but in recent years may have made her blush by telling West Wing aides the key to a successful marriage is “good sex.” REUTERS

Bernal holds more power than suggested by his vague job title and is “known to make life hell for junior aides who find him to be impatient, demanding, and overbearing,” according to the tome.

“At times, people close to her question just how aware Jill is of her enforcer’s abrupt nature, but she is not
unaware. She has told people who have grown frustrated with him that they need to bring up their concerns with him directly,” Rogers writes.

President Biden told his staff on his first day in office in 2021 that “I will fire you on the spot” if “I hear you treat another colleague with disrespect or talk down to someone.”

That pronouncement has led to several awkward situations for his administration — including when then-White House spokesman TJ Ducklo was exposed for vulgar and threatening behavior toward a female reporter in early 2021. Ducklo was allowed to resign and later joined Biden’s re-election campaign.

The first lady’s office did not dispute that she refers to Bernal, who is openly gay, as her “work husband.”

Bernal “can be the genesis of the drama, pitting staffers against each other and quizzing them about their loyalty to the Bidens, according to people who have observed his interactions,” the forthcoming book says.

“Bernal is also known to profess his love of and respect for his colleagues in the same breath as telling them they are disliked or disrespected in other parts of the building.”

“It’s like, ‘Oh my god, I love you, but did you know this person hates you?’ a former senior West Wing official said with a laugh, describing a typical interaction with Bernal,” Rogers writes.

“Another former senior West Wing official described him as a ‘trash talker, a little bit, about people — he’s not the only one in politics, but he is the only one with the ear of the First Lady.’ Several current and former White House officials and Bidenworld aides also say that Bernal has a signature move: upending projects at the last minute and, as one person put it, ”fixing’ the disaster that ensues.’”

Bernal “weighs in on everything from the Biden family’s schedules to the president’s motorcade routes,” Rogers writes.

“No order is beneath him: He wrangles the dog, carts the White House cat around in her cage, and makes sure that the various Biden children and grandchildren are transported to the appropriate weekend retreats. Camp David or Wilmington this weekend? Call Anthony.

“When the Bidens take vacations to Rehoboth, Bernal goes with them to make sure the two-minute walk to the beach is properly choreographed.”

A White House official told The Post Monday that Bernal is simply “direct” and usually correct in his pursuit of “high standards.”

“Anthony is one of the most generous, conscientious, brilliant people working at the White House. Is he direct? Yes. Is he often wrong, when he directly points out that something needs to be fixed? No,” the official said.

“Anthony would be the first to say he has high standards – as he should. We all should. This is the White House.”    

Democratic presidential candidate former Vice President Joe Biden hugs his wife Jill Biden
The first lady’s office did not dispute that she refers to Bernal, who is openly gay, as her “work husband.” AP/Andrew Harnik

The book quotes Bernal replying to criticism of his behavior, saying, “It is my job to make sure that we don’t make mistakes wherever possible.”

The first lady’s former chief of staff and current US ambassador to Spain Julissa Reynoso Pantaleón defended Bernal in a 2021 statement to Politico, saying: “There is no one at the White House with a bigger heart than Anthony, which is one of several reasons why so many in the First Lady’s office have worked with him for years. He cares deeply about the personal and professional growth of his colleagues.”

Although Bernal reportedly is known by the first lady as her “work husband” — earning credit for her continued teaching of community college courses but also her botched attempt to speak Spanish in public — surprising words attributed to her real-life husband also emerged in the book.

The nation’s oldest sitting president reportedly “has joked to aides that ‘good sex’ is the key to a lasting and happy marriage, much to his wife’s chagrin.”