Robert DeNiro has never sugarcoated it regarding his feelings for Trump. And in an op-ed on Wednesday he spoke directly to Robert Mueller:
...the country needs to hear your voice. Your actual voice. And not just because you don’t want them to think that your actual voice sounds like Robert De Niro reading from cue cards, but because this is the report your country asked you to do, and now you must give it authority and clarity without, if I may use the term, obstruction...
And if, in fact, you have nothing further to say about the investigation, for your public testimony, you could just read from the report in response to questions from members of Congress. Your life has been a shining example of bravely and selflessly doing things for the good of our country. I urge you to leave your comfort zone and do that again.
You are the voice of the Mueller report. Let the country hear that voice.