WASHINGTON—President Trump and the leaders of Mexico and Canada reached a deal to put tariffs on hold for a month, following separate telephone calls in which the U.S. neighbors agreed to take measures to fight fentanyl trafficking across the U.

President Donald Trump paused tariffs on Canada, Mexico for 30 days, but his ultimate trade strategy goals and objectives remain murky.

It’s an opportunity for Mexico to go after the cartels,” said Ray Donovan, the former DEA chief of operations.