A report from the Congressional Budget Office said that space-based interceptors, which do not currently exist, would probably consume 60 percent of the total cost.

The denials came after a CNN report claimed the C.I.A. had been involved in the assassination of a cartel member inside Mexico earlier this year.

The agreement, which reverses President Luis Abinader’s previous stance, is part of President Trump’s efforts to find governments willing to accept deportees.