New Jersey Gov. Chris Christie defended President Trump against a week of news which saw more revelations about the depth and nature of the ongoing Russia investigation.

Earlier in the week, the Wall Street Journal broke the news that special counsel Robert Mueller had impaneled a grand jury to help in his investigation, but Christie said the media reaction to this was overblown.

"This is a normal step taken by a careful prosecutor who's doing a thorough investigation," Christie began on CNN's "State of the Union." "I think that's exactly what Bob Mueller is doing. You can't issue subpoenas without a grand jury. It's the grand jury that actually issues the subpoenas. And so I think Bob Mueller wanted a grand jury focused on this so he could issue subpoenas and then review the evidence. That's a typical thing to be done in any investigation."

CNN also reported that the Mueller investigation was beginning to look more deeply into the finances of President Trump, and also of many of his campaign associates.

Christie, like Trump, warned that if the special counsel decided to follow the so-called "money trail," he would need to be extremely cautious in doing so.

"I trust that he'll be very careful to try not to go on a fishing expedition," Christie said. "There's always temptation to do that. I hope that that's not what he does. I hope the focus remains on what may have motivated any collusion between the Trump campaign and Russia, if, in fact, any collusion happened at all. So far, as you know, there is absolutely no evidence of any collusion at all between the trump campaign and the Russians. That's what investigations are for. I said all along, let the special prosecutor investigate it and let the chips fall where they may."