Washington (CNN) Former Republican presidential candidate Carly Fiorina on Thursday denounced Donald Trump's Twitter attack on Stormy Daniels earlier this week in which he referred to the adult film actress as "horseface."

"I think the habit of insulting one's political enemies is unfortunately long standing in this country, and he has brought it to a new low," Fiorina told CNN's Anderson Cooper on "Anderson Cooper 360."

Trump made the comment Tuesday after a federal judge dismissed Daniels' defamation lawsuit against the President for deriding Daniels' account of an affair with Trump with subsequent threats from an unknown men not to come forward with her story.

"Great, now I can go after Horseface and her 3rd rate lawyer in the Great State of Texas," he tweeted in celebration of the ruling. "She will confirm the letter she signed! She knows nothing about me, a total con!"

Fiorina, a former Hewlett-Packard executive, had her own appearance attacked by then-candidate Trump during the 2016 election. "Look at that face," he told Rolling Stone magazine of Fiorina. "Would anyone vote for that? Can you imagine that, the face of our next president?!"

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