Trump's unsuccessful rival for the Republican presidential nomination says the new tenant in the White House has made "some really good appointments" and acted "decisively" on rolling back regulations -- but he is very critical of Trump's style.
"He hasn't shifted to being president in a way that people are used to and I think that's the problem," Bush told the television show "Facing South Florida" on CBS Miami.
"He should stop saying things that aren't true," he said about Trump's daily Twitter bursts.
"He has got a lot of work to do and some of these things - the wiretapping, all this stuff - is a complete distraction that makes it harder to accomplish the things I know he wants to do."
Bush, who served as governor of Florida, is the son of the 41st president George H.W. Bush and brother of the 43rd, George W. Bush.
Asked whether Trump's tweets diminish the office of the president, he replied, "A little bit, yeah."
"It's one thing to do it as a candidate," he added. "When you are the president, your words have consequences."
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