Story highlights Christie said he saw no reason for Mueller to step down

Trump later Sunday morning again denounced the questions about alleged collusion with Russia

Washington (CNN) The news that a federal grand jury has approved charges in special counsel Robert Mueller's Russia probe should concern those under investigation, New Jersey Republican Gov. Chris Christie said Sunday.

"I think anybody who's been advised by the special counsel's office that they're a target of the investigation -- which I'm sure he has done to those people who are -- should be concerned," Christie said in interview with CNN's Jake Tapper on "State of the Union."

CNN reported Friday that a federal grand jury approved the first charges from Mueller's investigation and that anyone charged could be taken into custody as soon as Monday.

Christie, a former US attorney, said leaks to the news media about the grand jury's actions could undermine the credibility of the process, which he said needed to remain confidential.

While some in his own party, including Christie himself, have suggested that Mueller should resign from the Russia investigation if he has any conflicts of interest, the New Jersey governor said Sunday that he saw no reason at this point for Mueller to do so.

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