Kentucky Sen. Rand Paul hit back at New Jersey Gov. Chris Christie in the two Republicans’ ongoing spat over national security.

Christie last week criticized Paul’s opposition to warrantless federal surveillance programs, saying it harmed efforts to prevent terrorism. Paul told reporters after speaking at a fundraiser outside Nashville on Sunday that Christie’s position hurts GOP chances in national elections, and that spending priorities of critics like the governor and Rep. Peter King of New York do more to harm national security.