He said in a tweet Saturday he would delay for two weeks to give lawmakers time to discuss border solutions.
Three administration officials told The Associated Press the operation had been canceled because details had leaked in the media and officer safety could be jeopardized. The officials were not authorized to speak publicly on the operation and spoke on condition of anonymity.
The operation was expected to begin Sunday and would have targeted people with final orders of removal, including families whose immigration cases had been fast-tracked by judges.
Trump earlier this week tweeted that an operation was upcoming and said the agency would begin to remove "millions" of people.