Inside the White House, the president’s advisers are concerned that he has repeatedly referred to Dreamers, many of whom are in their 20s and 30s, in such sympathetic and politically loaded terms. “Our immigration folks are like, ‘Stop calling them kids,’” Mr. Spicer said.

The president is weighing a variety of strategies for dealing with the roughly 840,000 Dreamers, according to senior officials, including Mr. Priebus, and lawmakers of both parties in Congress have been trying to devise legislation to carve out a special status for them. For the time being, Mr. Trump’s administration is still issuing work permits to undocumented people under the program, leaving their protection intact even if their fate is in limbo.

The delay has outraged supporters of Mr. Trump’s who took his vows to rescind President Barack Obama’s program, called Deferred Action for Childhood Arrivals, very seriously.

“He’s really starting to anger his base with this,” said Roy Beck, the president of NumbersUSA, a group that works to reduce immigration. “I’ve got people really angry and talking about ‘He’s double crossed us, he’s deceived us.’ You could say that the troops are restless, and I can’t blame them.”…

“His promise on DACA was pretty clear and unequivocal,” said Mark Krikorian of the Center for Immigration Studies, a group that advocates strong immigration restrictions. That would be a “pretty basic thing” to renege on, he said, “right in the beginning of an administration.”