President Donald Trump criticized former Special Counsel Robert Mueller for bringing his top aide Aaron Zebley to assist him while testifying to Congress on Wednesday.

“So Robert Mueller has now asked for his long time Never Trumper lawyer to sit beside him and help with answers,” Trump wrote. “What’s this all about?”

Trump pointed out that Zebley was the former lawyer for Justin Cooper, the IT aide who helped Hillary Clinton set up her private email server and helped destroy her Blackberry email devices with a hammer.

“This should NOT be allowed,” he wrote. “Rigged Witch Hunt!”

Zebley’s appearance at the hearing also drew criticism from House Republicans.

“You don’t get to change the rules right before kickoff, especially after a 22 month, $30 million investigation,” Congressman Jim Jordan wrote on Twitter.

Rumor is that Aaron Zebley (Mueller’s Chief of Staff) will be on the witness panel with Mueller. You don’t get to change the rules right before kickoff, especially after a 22 month, $30 million investigation. — Rep. Jim Jordan (@Jim_Jordan) July 23, 2019

Trump said that Zebley’s role assisting Mueller was never part of the agreement.

“This was specifically NOT agreed to, and I would NEVER have agreed to it,” he wrote. “The Greatest Witch Hunt in U.S. history, by far!”

Trump revisited some of his criticism of Mueller and the investigation, calling it one-sided and politically biased.

“So Democrats and others can illegally fabricate a crime, try pinning it on a very innocent President, and when he fights back against this illegal and treasonous attack on our Country, they call It Obstruction?” he wrote. “Wrong!”

The president also asked why the investigators never spent time investigating his opponents.

So Robert Mueller has now asked for his long time Never Trumper lawyer to sit beside him and help with answers. What’s this all about? His lawyer represented the “basement server guy” who got off free in the Crooked Hillary case. This should NOT be allowed. Rigged Witch Hunt! — Donald J. Trump (@realDonaldTrump) July 24, 2019

So Democrats and others can illegally fabricate a crime, try pinning it on a very innocent President, and when he fights back against this illegal and treasonous attack on our Country, they call It Obstruction? Wrong! Why didn’t Robert Mueller investigate the investigators? — Donald J. Trump (@realDonaldTrump) July 24, 2019

It was NEVER agreed that Robert Mueller could use one of his many Democrat Never Trumper lawyers to sit next to him and help him with his answers. This was specifically NOT agreed to, and I would NEVER have agreed to it. The Greatest Witch Hunt in U.S. history, by far! — Donald J. Trump (@realDonaldTrump) July 24, 2019

Why didn’t Robert Mueller & his band of 18 Angry Democrats spend any time investigating Crooked Hillary Clinton, Lyin’ & Leakin’ James Comey, Lisa Page and her Psycho lover, Peter S, Andy McCabe, the beautiful Ohr family, Fusion GPS, and many more, including HIMSELF & Andrew W? — Donald J. Trump (@realDonaldTrump) July 24, 2019

It has been reported that Robert Mueller is saying that he did not apply and interview for the job of FBI Director (and get turned down) the day before he was wrongfully appointed Special Counsel. Hope he doesn’t say that under oath in the we have numerous witnesses to the….. — Donald J. Trump (@realDonaldTrump) July 24, 2019

….interview, including the Vice President of the United States! — Donald J. Trump (@realDonaldTrump) July 24, 2019