Washington CNN  — 

Senate Judiciary Committee Chairman Chuck Grassley said Wednesday he hopes President Donald Trump does not try to direct him to “take control” of the Russia probe.

Grassley, the Iowa Republican who leads Senate oversight of the Justice Department, was responding to a tweet from Trump where the President called on his party to “take control” of the probe into potential coordination between his associates and Russia, insisting it is the “single greatest” witch hunt in US history.

Asked by CNN’s Manu Raju about the tweet, Grassley said, “I don’t know what the President has in mind, and I don’t think I better comment until I have a discussion with the President on that point, and I don’t intend to have a discussion with the President on that point, and I hope he doesn’t call me and tell me the same thing that you said he said.”

Shortly before the “control” tweet, Trump sent one labeling California Democratic Sen. Dianne Feinstein as “sneaky” and slammed her for releasing testimony Tuesday from the August questioning of the co-founder of Fusion GPS, the company that hired the author of the dossier of allegations about Trump and Russia.

Grassley told CNN he opposed Feinstein’s decision and contended the release would make voluntary testimony from future witnesses more difficult. Asked if that meant Trump son-in-law Jared Kushner was no longer of interest to the committee, Grassley said, “no, not at all.”

“These transcripts would have been released eventually anyway,” Grassley said. “I think it does create some problems, for instance when you’re getting people to voluntarily come to you, it may make a lot of people a little more reserved about whether or not they want to cooperate.”

Utah Republican Rep. Chris Stewart, who sits on the House Intelligence Committee, said in an interview on CNN’s “Newsroom” that he did not agree with Trump that the investigation is a “witch hunt,” but that he understands “what the President is feeling” due to the severity of allegations against him and his associates.