Mexican President Andres Manuel Lopez Obrador said Monday that tensions with the United States over the case of a former defense minister accused of cartel ties would not affect cooperation.

The US Justice Department on Saturday threatened to end law enforcement collaboration with Mexico after Lopez Obrador accused the US Drug Enforcement Administration (DEA) of fabricating evidence.

US authorities said that Mexico's publication of more than 700 pages of investigative materials in the case of retired general Salvador Cienfuegos had violated an agreement between the two countries.

Lopez Obrador, however, insisted that Mexico had "acted properly" and that ties between the neighbors would not be damaged.

"Relations with the current government are good ... and that will continue with the new administration of President Biden," Lopez Obrador told reporters.

Cienfuegos, a key figure in ex-president Enrique Pena Nieto's 2012 to 2018 government, was accused by the US of conspiring to produce and distribute "thousands of kilograms" of cocaine, heroin, methamphetamine and marijuana.

This file photo from March 5, 2012 shows then US Vice President Joe Biden (L) shaking hands with then candidate and now Mexican president Andres Manuel Lopez Obrador in Mexico City; the two countries have clashed over cooperation on drug matters
This file photo from March 5, 2012 shows then US Vice President Joe Biden (L) shaking hands with then candidate and now Mexican president Andres Manuel Lopez Obrador in Mexico City; the two countries have clashed over cooperation on drug matters AFP / Yuri CORTEZ

His arrest at a Los Angeles airport in October -- on charges that could have resulted in a life sentence -- had surprised the Mexican government, which successfully pushed for him to be sent home to face possible prosecution.

On Thursday, Mexican prosecutors exonerated the 72-year-old, rejecting the US allegations.

The US Justice Department said Mexico's action was disappointing and "calls into question whether the United States can continue to share information to support Mexico's own criminal investigations."

Lopez Obrador said his government had decided to release the voluminous US case file "so that it would be known, without hiding anything... that the crimes were in fact fabricated."

Asked about the US reaction, he added: "I could also say the same -- we are disappointed with the work of the DEA."

Mexican lawmakers last month approved security law reforms pushed by Lopez Obrador stripping DEA and other foreign agents of diplomatic immunity, to the dismay of US authorities.

Lopez Obrador's relations with President-elect Joe Biden had already gotten off to a rocky start; he was one of the last high-profile leaders to congratulate the former vice president on his election victory, saying he wanted to wait until legal disputes were resolved.

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