WATCH: Trump insists he isn't agitated by Mueller -- then rages against 'witch hunt' Russia investigation
President Donald Trump. (Screenshot)

President Donald Trump on Friday denied that he was agitated by special counsel Robert Mueller's Russia investigation. But he quickly attacked the investigation as a "hoax" and "witch hunt."

"I'm not agitated, it's a hoax," Trump said. "The whole thing is a hoax."

A reporter in the White House noted that Trump seemed particularly unhappy with Mueller on Thursday morning.

"No, it's just a continuation," Trump replied. "You can go -- there should have never been an investigation because there was never anything done wrong. There was no collusion."

"You would have known about it a long time ago if there was. There was nothing -- they should have never had it. They have wasted millions and millions of dollars," the president continued.

Trump described the investigation as a "witch hunt," but insisted that Mueller would not cause problems for him. "I'm sure it will be just fine," he remarked.

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