Colombia will use drones to resume spraying of coca crops with a weed killer, the government announced on Dec. 22 as authorities grapple with record levels of cocaine production that have fueled tensions with the U.S. administration.

The South American country banned aerial fumigation of coca crops in 2015, after the World Health Organization put glyphosate — the weed killer used by spray planes — on a list of carcinogens.

Justice Minister Andrés Idárraga told a news conference that the new action involving high-tech drones was approved by the government and would begin on Dec. 25.

He said the drones would be sent to areas where gangs and rebel groups are forcing peasants to grow coca, the primary source of cocaine. “Our security forces will be safer” that way, Idárraga added.

Environmental activists had long warned that small airplanes spraying coca fields — often flown by U.S. contractors — were also dumping their chemicals on legal crops and into streams, polluting vulnerable ecosystems and exposing villagers to contaminated water.