President Trump said he was weighing using the power of the government against one of his longtime entertainment world nemeses, the comedian and actress Rosie O’Donnell, threatening to revoke her citizenship.

Shortly before 10 a.m. on Saturday, Mr. Trump said on Truth Social, “Because of the fact that Rosie O’Donnell is not in the best interests of our Great Country, I am giving serious consideration to taking away her Citizenship.”

The president called Ms. O’Donnell a “threat to humanity” and said she should stay in Ireland, where she moved to in January after Mr. Trump won a second term.

Mr. Trump’s headline-grabbing provocation about Ms. O’Donnell comes at a moment in which his administration is contending with criticism on many fronts: His top law enforcement officials are bitterly feuding over the Jeffrey Epstein saga; there remain unanswered questions about the decision to halt munitions to Ukraine and who authorized it; the homeland security chief is facing intense scrutiny over FEMA’s response in Texas; and so on.

Ms. O’Donnell snapped back at Mr. Trump with her own barrage of insults on Instagram.

“The president of the USA has always hated the fact that I see him for who he is — a criminal con man sexual abusing liar out to harm our nation to serve himself,” she said. “This is why I moved to Ireland.”

She further taunted the president in a subsequent post showing a photo of Mr. Trump with Jeffrey Epstein, taken in 1997 in Palm Beach, Fla.

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