Former Special Counsel Robert Mueller is not an "adversary" for Republicans, and could actually be a contrarian force that works in favor of President Trump, according to Karl Rove.

Appearing on “America’s Newsroom” with anchor Bill Hemmer, Rove said: “If you look at it before the Mueller report was issued and after the Mueller report issued two things happened: the president’s approval and disapproval ratings stabilized and began to rise. They’d hit a low point in the high thirties. Now they’re sort of in the mid-forties.

“Second of all, the percentage of people who said they opposed impeachment grew after the Mueller report was released. Dramatically among independents, the swing voters who will decide next year’s election.”

Rove’s comments come ahead of Mueller’s highly anticipated public appearance before the House Intelligence and House Judiciary Committees on Wednesday morning. A reluctant witness, Mueller agreed to appear before the committees under a subpoena.

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His testimony is not expected to stray too far from the contents of the 448-page report released in April. According to The Washington Post, Mueller plans to submit the publicly available version of his report as a statement for the record.

Nevertheless, on Monday the Department of Justice (DOJ) instructed Mueller not to answer a wide variety of questions about his investigation of the president and Russian interference in the 2016 election.

Associate Deputy Attorney General Bradley Weinsheimer said in a letter that he was responding to a request earlier this month from Mueller for guidance on how to handle questions “concerning privilege or other legal bars applicable to potential testimony in connection with” subpoenas for his congressional testimony.

The testimony -- to the chagrin of lawmakers on both sides of the aisle -- Weinsheimer stated, "must remain within the boundaries of your public report because matters within the scope of your investigation were covered by executive privilege."

DOJ TELLS MUELLER HIS TESTIMONY 'MUST REMAIN WITHIN THE BOUNDARIES' OF PUBLIC REPORT

"As the Attorney General has repeatedly stated, the decision to testify before Congress is yours to make in this case, but the Department agrees with your stated position that your testimony should be unnecessary under the circumstances," Weinsheimer wrote.

Weinsheimer told Mueller that DOJ policy prevents him from commenting on the legal conclusions his office made "with respect to uncharged individuals, other than information contained within the portions of your report that already have been made public."

Weinsheimer also said Mueller should not testify about portions of the report that have been redacted or are about uncharged third parties.

“Please note there should be no testimony concerning the redacted portions of the public version of your report,” the letter said, and reminded Mueller that the prosecution of Trump adviser Roger Stone and a separate case are still awaiting trial, “and local court rules and specific orders issued in those cases substantially restrict the Department’s ability to make public statements about those cases.”

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President Trump told reporters on Monday that he’d maybe “see a little bit of it” and that: “We had a total no collusion finding. The Democrats were devastated by it, they went crazy, off the deep end…The Attorney General based on the report was easily able to find there was no obstruction. There's no nothing. They're wasting their time.”

Gesturing to his trademark whiteboard, Rove told Hemmer that Democrats are going to spend a lot of time tomorrow on obstruction. He said all Republicans have to do is, “remind that the Mueller report said that they, ‘…did not find that the Trump campaign, or anyone associated with it, conspired or coordinated with the Russian government.’”

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“And, whenever they bring up one of these instances that filled up the second half of the Mueller report,” said Rove, “the Republicans just need to ask Mueller, ‘Do you still stand by the statement in your report that ‘…this report does not conclude that the president committed a crime?’ Do you still stand by that finding, Director Mueller?”

By doing so, Rove says that Republicans will be able to “help continue the progress that the president has enjoyed ironically as a result of the Mueller report, which is it is stabilized as his favorable and unfavorable and driven up the percentage of people who say they oppose impeachment.”