Trump said Tuesday the U.S. is ready to "wage war" on the drug cartels and "wipe them off the face of the earth" after at least 10 members of a prominent Mormon family were killed in an ambush attack near U.S.-Mexico border.
In a series of tweets, Trump said the U.S. was willing to aid Mexico in "cleaning out these monsters" and that "sometimes you need an army to defeat an army."
"We merely await a call from your great new president!" he said.
At his daily morning press conference on Tuesday, López Obrador, who was inaugurated last December, declined the offer, saying, "it's not in agreement with our convictions. The worst thing is war."
López Obrador has faced fierce internal criticism for his decision to release Ovidio Guzmán, the son of drug kingpin Joaquín "El Chapo" Guzmán, after cartel gunmen besieged the northern city of Culiacán, killing 13 people, on Oct. 17.
Trump's offer to wage war against the cartels using U.S. forces in Mexico touches a third rail of Mexican politics, given the history of U.S. intervention in the country.
And it runs afoul of López Obrador's campaign pledge to end the long-running drug war, which he blames on former President Felipe Calderón, his political nemesis.