The case prompted the government to threaten a review of agreements allowing US agents to operate in Mexico.
Mexico said on Friday that the United States Drug Enforcement Administration (DEA) should carry out an internal investigation into the conduct of its case against a former defence minister, in a new test of bilateral ties with US President Joe Biden’s government.
Mexican President Andres Manuel Lopez Obrador said the investigation should look into who within the DEA “fabricated” the case against former minister Salvador Cienfuegos, days after Mexico’s attorney general decided to drop charges.
“I am not going to go to any international body, but I respectfully believe that agency should do an internal investigation and clarify what happened, who made the file, who gave the order to apply it,” Lopez Obrador said, referring to the DEA, during a regular news conference.
Both governments later confirmed that Lopez Obrador and Biden would speak by phone on Friday afternoon.
The US arrest and subsequent release of Cienfuegos put severe strain on bilateral security cooperation. Mexico retaliated with restrictions on DEA intelligence gathering. Lopez Obrador also angered Washington by publishing a large dossier from the case that the US had provided in confidence.
The ongoing fallout risks further souring ties just as Biden takes over from former US President Donald Trump, with whom the Mexican president had struck an unlikely friendship.
Teneo, a political risk consultancy, said Lopez Obrador’s recent moves seemed “deliberately provocative” to the new US administration.
His “contrarian attitude is largely due to his drive to acquire leverage ahead of what he anticipates will be a more complex period in bilateral relations,” Teneo’s Nicholas Watson said in a note shared with the news agency Reuters.
Under Trump, in return for a hardline stance on immigration, Lopez Obrador received little high-level US pressure over his push for more state control in the energy sector.
Cienfuegos, a member of former President Enrique Pena Nieto’s government, was arrested in October at Los Angeles International Airport and accused by US prosecutors of collaborating with a splinter of a powerful drug cartel.
He returned to Mexico in November after a federal judge granted a US government request to drop charges against him and turn the investigation over to Mexico, citing diplomatic sensitivities.
The Mexican attorney general’s office said earlier in January that the US case was not strong enough to warrant charges against Cienfuegos, a decision Lopez Obrador publicly backed.
Lopez Obrador said the evidence the DEA provided, which stretched for hundreds of pages and which he ordered to be shared publicly online, was riddled with inconsistencies.
“There is no way that we are going to invent crimes,” said Lopez Obrador. “We have said that if the DEA has additional information to present it.”
The US embassy in Mexico City referred Reuter’s request for comment to the US Department of Justice. A spokesman for the DEA, a division of Justice, did not immediately respond.