MEXICO CITY (Reuters) - Talks between Mexico and the United States to stave off tariffs dragged on Friday as negotiators battled over a U.S. demand that Mexico accepts more Central American migrants under a concept know as “safe third country,” two Mexican sources said.

Trump has threatened to impose the levies starting at 5% on June 10 if the Mexican government does not agree to do more to tackle an increase in mostly Central American migrants crossing Mexico to enter the United States.