(CNN) Michael Cohen, the President's former fixer and ultimate loyalist, is sending a clear signal to President Donald Trump and his attorney, Rudy Giuliani, that "the truth is not you(r) or your client's friend," according to sources with knowledge of Cohen's thinking.

Two sources familiar with Cohen's thinking say he has "hit the reset button" and is continuing his commitment to speak the "real truth."

In particular, the same sources say Giuliani is wading into dangerous territory when he asks Cohen to "tell the truth" about the Trump Tower meeting with Donald Trump Jr. and Russian meddling in the election.

For the past year, Cohen has vehemently denied participating in or knowing about any collusion with Russia during the 2016 campaign. These new comments from sources close to Cohen suggest he might have information about Trump and others in the President's orbit to share with investigators, though Cohen hasn't publicly revealed any details yet.

Cohen believes that Giuliani and the President are trying to send him a message, a source familiar with Cohen's thinking said. Cohen feels the message is that if he crosses them, they will continue their "attacks" on his character and say that he is lying. Cohen is referring all inquiries to his attorney, Guy Petrillo.

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