Ex-'CBS Evening News' anchor Dan Rather blasted President Trump Thursday, calling him the "biggest purveyor of fake news" amid Trump's ongoing feud with the media.

During his appearance on "The Dan Abrams Show" on Thursday, Rather admitted that journalists "make mistakes," but insisted that was different from "fake news."

“If you want to make the conversation about fake news — which I do not — the single biggest purveyor of fake news in the country is unfortunately, and there’s no joy in saying this, the President of the United States,” Rather said.

“Put what he tweets out ... and have it fact-checked — for example, the Washington Post does this — and you’ll find that he's the biggest purveyor of fake news around."

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“I’m a little frustrated that those of us in journalism have not made the point strongly enough,” Rather continued.

“When you call everybody in the press ‘enemies of the people,’ try to indict all of the press, he’s done the same thing with the courts, he’s done the same thing with Congress. There’s a pattern here ... He has sought to undermine every portion of our system of checks and balances.”

Rather, 87, retired from CBS in 2005, months after airing unverified documents in a report about President George W. Bush’s service in the Texas Air National Guard prior to the 2004 election. He now makes frequent appearances on CNN and MSNBC.