Fox News made light of Donald Trump’s latest threat not to attend the next GOP presidential debate on Thursday, after the candidate posted a video claiming that moderator Megyn Kelly is biased against him and would treat him unfairly.

“We learned from a secret back channel that the Ayatollah and Putin both intend to treat Donald Trump unfairly when they meet with him if he becomes president — a nefarious source tells us that Trump has his own secret plan to replace the Cabinet with his Twitter followers to see if he should even go to those meetings,” Fox said in a tongue-in-cheek statement.

Trump posted a video on Instagram in which he said, “Megyn Kelly is really biased against me. She knows that. I know that. Do you think that she can be really fair at a debate?” He also posted a vote in which Twitter users can answer his question, “Should I do the #GOPdebate?” As of 3 p.m. ET, “yes” votes were slightly outpacing “no” votes.

Trump has threatened to pull out of previous debates, and even suggested that CNN should pay him to show up to their debates, with the proceeds going to a veterans organization. The network did not. He and Ben Carson threatened to pull out of a CNBC debate in late October unless the time was kept to two hours, among other demands. They did attend after discussions between the network and the Republican National Committee.

Fox News is partnering with Google for the debate, to be held in Des Moines, Iowa. Bret Baier and Chris Wallace are joining Kelly as moderators. The debate is the final GOP gathering before the Iowa caucus on Monday.