WASHINGTON — President Trump publicly pushed back Thursday against a characterization by White House Chief of Staff John Kelly that the president’s views on a southern border wall had “evolved” and privately fumed about the episode.

“The Wall is the Wall, it has never changed or evolved from the first day I conceived of it,” the president said in a morning tweet. “Parts will be, of necessity, see through and it was never intended to be built in areas where there is natural protection such as mountains, wastelands or tough rivers or water.”

Trump’s comments on Twitter came a day after Kelly told Democratic lawmakers that some of the hard-line immigration policies Trump advocated during the campaign were “uninformed,” that the United States will never construct a wall along its entire southern border and that Mexico will never pay for it, according to people familiar with the meeting.

Later Wednesday, Kelly confirmed his comments during a television interview but attempted to play down differences with the president.

“He has evolved in the way he looks at things,” Kelly told Fox News. “Campaign to governing are two different things, and this president has been very flexible in terms of what’s in the realm of the possible.”

Trump had only positive things to say about Kelly when talking to reporters Thursday, but several Trump associates said the president was furious with his chief of staff both for what he said and for the tone he used, which Trump thought made it appear he was a child who had to be managed.

One Trump associate who spoke to the president Wednesday night said Trump thought Kelly’s comments made him look bad and like he was giving in to Democrats.

The president, this person said, particularly disliked the word “uninformed” that appeared in news reports and has chafed for weeks at the characterization of himself as not intelligent and flighty in the best-selling book about his presidency by Michael Wolff.

The person, who spoke on the condition of anonymity to talk more candidly, said it was “inevitable” for Trump to be angry with his chief of staff and that it was surprising that it hadn’t happened before.

It was a positive sign for Kelly, the person said, that Trump didn’t mention the chief of staff’s name explicitly in the tweet. There seems to be no effort afoot to make a change in the chief of staff position, the person said.

Christopher Ruddy, a Trump friend and president of the conservative media outlet Newsmax, agreed with that assessment, although he said he has not spoken with the president since Kelly made his remarks.

“The president is pretty happy with his job overall,” Ruddy said of Kelly.