The Mexican ambassador to the United States, Esteban Moctezuma, stated on Friday that the majority of seized fentanyl at the border is trafficked by US citizens.

"We are seeing that in 85 percent of the seizures at the border made by CBP (US Customs and Border Protection), the individuals transporting the drugs are not migrants, but American citizens," he said at a press conference in Washington alongside the US ambassador to Mexico, Ken Salazar.

Moctezuma emphasized that both nations have a responsibility to combat it and highlighted Mexico's efforts to prevent the arrival of chemicals from Asia, used in drug production, into its territory.

Fentanyl is a potent synthetic opioid that, according to Washington, is manufactured by Mexican cartels using chemicals from China and trafficked to the United States, where over 70,000 people died last year due to overdoses of this substance.