Donald Trump and Megyn Kelly Credit: Rhona Wise/AFP/Getty Images: Taylor Hill/Getty Images

Fox News had some harsh words for Donald Trump on Friday, March 18, after the Republican presidential hopeful slammed journalist Megyn Kelly on Twitter.

“Everybody should boycott the @megynkelly show,” Trump, 69, tweeted Friday. “Never worth watching. Always a hit on Trump! She is sick, & the most overrated person on tv.”

The real estate mogul’s latest rant comes hot on the heels of his decision to skip a GOP debate in Salt Lake City that was set to air on Fox News. (Trump previously refused to take part in a Republican debate in Iowa because of his ongoing feud with Kelly, 45, who was one of the moderators.)

The Salt Lake City debate has since been canceled.

On Friday, the news network quickly defended Kelly, calling Trump’s attack repugnant.

“Donald Trump’s vitriolic attacks against Megan Kelly and his extreme, sick obsession with her is beneath the dignity of a presidential candidate who wants to occupy the highest office in the land,” Fox News said in a statement. “Megyn is an exemplary journalist and one of the leading anchors in America — we’re extremely proud of her phenomenal work and continue to fully support her throughout every day of Trump’s endless barrage of crude and sexist verbal assaults.”

The former Apprentice star seemed undeterred by Fox's criticism and continued his Twitter rant against Kelly on Saturday.

"Crazy @megynkelly says I don't (won't) go on her show and she still gets good ratings. But almost all of her shows are negative hits on me!" he wrote. "If crazy @megynkelly didn't cover me so much on her terrible show, her ratings would totally tank. She is so average in so many ways!"

The trouble between Trump and Kelly started after a GOP debate in August 2015, when the Fox News journalist quizzed the real estate mogul about his prior reference to women as “fat pigs,” “slobs” and “disgusting animals.”

Trump fired back that he only said those phrases in reference to longtime nemesis Rosie O’Donnell.

He later took to Twitter to call Kelly a “loser” and a “bimbo” and said in a CNN interview that the reporter had “blood coming out of her eyes — blood coming out of her whatever.”

Trump has since frequently bashed Kelly on social media, asserting that she was unfair toward him in the Republican debates.

"Pathetic attempt by @foxnews to try and build up ratings for the #GOPDebate. Without me they'd have no ratings!" he wrote in January before announcing his decision to boycott the Iowa debate.

He also posted a video on his Instagram account stating, "Megyn Kelly is really biased against me. She knows that. I know that. Everybody knows that. Do you think she can really be fair at a debate?"

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