A former adviser to three Republican presidents called the speech Donald Trump gave before a crowd of supporters Saturday in Pennsylvania the “most divisive” he has ever heard from a president.

David Gergen, a CNN political analyst who advised GOP Presidents Richard Nixon, Gerald Ford and Ronald Reagan — and Democratic President Bill Clinton — said he found the speech “deeply disturbing” with little change from Trump’s bombastic, divisive campaign messages.

Trump slammed the press — again ― as “fake news,” vowed to topple Obamacare and promised to build the border wall between Mexico and the U.S. “Don’t worry, we’re going to have the wall,” Trump said at the rally marking his 100th day as president. “Rest assured. Go home, go to sleep.”

Gergen said on a CNN panel following Trump’s speech that bringing “your campaign speech into the presidency is something presidents rarely do.” He added: “I think this is the most divisive speech I’ve ever heard from a sitting American president.”

He “played to his base,” Gergen added. “He treated his other listeners — the rest of the people who have been disturbed about him or oppose him — he treated them basically as, ‘I don’t care, I don’t give a damn what you think because you’re, frankly, the enemy.’”

Gergen added: “I thought it was a deeply disturbing speech.”