Comedian Rosie O'Donnell, one half of a much-publicized and well-remembered 2006 feud with real estate tycoon Donald Trump, was aiming for payback last week when she dubbed the mogul's presidential campaign a "nightmare."

O'Donnell, who starred in hit movies including "Sleepless in Seattle" (1992) and "The Flintstones" (1994), was asked about Trump's White House aspirations as she discussed a guest starring role on Wednesday's episode of Fox's drama series "Empire," The Associated Press reported.

"It's a nightmare," the 53-year-old actress said, but did not elaborate. "That's my quote."

O'Donnell -- an outspoken liberal and activist for lesbian, gay, bisexual and transgender rights -- seemingly clashes with virtually all of Trump's policy proposals, Entertainment Weekly commented. But the actress has also made no effort to hide her personal animosity toward the billionaire business owner, whom she once called a "snake-oil salesman."

Most of the barbs from O'Donnell's side were made on ABC's "The View," the daytime women-oriented talk show the actress hosted after she replaced journalist Meredith Vieira in September 2006 and where she served as the counterweight to conservative commentator Elisabeth Hasselbeck.

The argument goes back to the mid-2000s, when O'Donnell criticized Trump for reinstating then-Miss USA Tara Conner. The contestant had initially been dethroned because of allegations of underage drinking and heavy drug use. Pointing to the tycoon's multiple marital affairs and controversial bankruptcies, the actress claimed that Trump was now using the scandal to "generate publicity for the Miss USA Pageant."

In response, Trump called the "I'll Do Anything" star names and threatened to sue O'Donnell, a threat that never came to fruition.

The GOP White House hopeful was asked about the incident at this year's first Republican presidential debate. Moderator Megyn Kelly inquired about the candidate's history of calling women "fat pigs," "dogs," "slobs" and "disgusting animals," the Washington Examiner recalled.

"Only Rosie O'Donnell," Trump, who later challenged Kelly's questions as inappropriate, replied in an apparent attempt to justify his behavior.