The Drug Enforcement Administration on Monday announced the launch of Gatekeeper, a binational collaboration to identify Mexican cartel leaders in smuggling corridors along the Southwest border.

MEXICO CITY (AP) — Mexico President Claudia Sheinbaum denied her administration had an agreement with the U.S. Drug Enforcement Administration Tuesday, hours after the U.S. agency announced “a major new initiative” to collaborate in the fight against drug cartels.

Drug Enforcement Administration officials plan to work with their counterparts in Mexico to target the gatekeepers of the smuggling corridors between the two nations. The effort is called Project Portero.