GOP frontrunner Donald Trump has not decided yet whether he plans to attend Thursday night’s Republican presidential debate. Why? Because he said he dislikes Megyn Kelly, an anchor with Fox News, which is the network set to host the debate.

Trump reiterated his strong distaste for Kelly in a recent interview with CNN. The leading candidate’s comments represent the latest in a quarrel that has extended back to the first debate in August. At that time Kelly, a moderator, provoked Trump’s ire by quoting some of his denigrating remarks about women and asking him whether they might hurt his bid in a general election.

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“You and Megyn Kelly have had issues,” said CNN’s Wolf Blitzer. “Are you going to be at that Fox debate?”

“Probably,” Trump began, before proceeding to bash Kelly, saying, “I might be the best thing that ever happened to her.” Then he became less resolute. “I would like to go to the debate,” Trump said. “I enjoy the debates. I’ve done well in the debates. Every single poll has said I’ve won every debate. But we’re going to see what happens.”

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“When you say probably,” Blitzer asked, “you haven’t 100% decided that you’ll be in attendance?”

“No, not 100%.”

“Why not?”

“I’m not 100%. I’ll see,” Trump said. “If I think I’m going to be treated unfairly, I’d do something else. I don’t think she can treat me fairly. I think she’s very biased. But that doesn’t mean I don’t do the debate. I like doing debates.”

“I want to do the debates,” he continued. “They’re good for me. But I don’t think she can treat me fairly. And I’m not a big fan of hers.”

Fox News responded to Trump’s comments with a statement of its own: “Sooner or later Donald Trump, even if he’s president, is going to have to learn that he doesn’t get to pick the journalists—we’re very surprised he’s willing to show that much fear about being questioned by Megyn Kelly.”

Kelly, host of Fox’s The Kelly File, has mostly remained above the fray, declining to engage Trump directly in the feud. Trump has yet to skip a debate, though he has threatened to do so before.