(CNN) Former first lady Michelle Obama discusses her dislike of President Donald Trump — as well as personal details of her life before and during her time in the White House — in her highly anticipated memoir, "Becoming," The Washington Post reported Thursday.

Obama says she would "never forgive" Trump for the rumors he spread questioning the legitimacy of President Barack Obama's American birth certificate , which she said threatened her family's safety.

"What if someone with an unstable mind loaded a gun and drove to Washington? What if that person went looking for our girls?," she wrote, according to the Post, which obtained an early copy of the book. It will be released next Tuesday. "Donald Trump, with his loud and reckless innuendos, was putting my family's safety at risk. And for this I'd never forgive him."

Trump responded to Obama's book Friday morning, telling reporters: "She got paid a lot of money to write a book and they always expect a little controversy."

He added that he would never forgive her husband Barack Obama "for what he did to our US military."

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