MEXICO CITY (Reuters) - Mexico said on Friday the U.S. Drug Enforcement Administration should carry out an internal investigation into the conduct of its case against a former defense minister, in a new test of bilateral ties with U.S. President Joe Biden’s government. 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,” said Lopez Obrador, 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 U.S. 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 United States had provided in confidence. The ongoing fallout risks further souring ties just as Biden takes over from Donald Trump, with whom the Mexican president had struck an unlikely friendship. Just on Thursday, Lopez Obrador said another phone call with Biden was not needed after the two men spoke in December. Teneo, a political risk consultancy, said Lopez Obrador’s recent moves seemed “deliberately provocative” to the new U.S. 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. Under Trump, in return for a hardline stance on immigration, Lopez Obrador received little high-level U.S. pressure over his push for more state control in the energy sector. While tensions over Cienfuegos have simmered in the first days of Biden’s administration, Lopez Obrador also praised him for quick action on immigration reform. Mexico has kept up its cooperation on immigration issues, including putting pressure on Central American governments to break up the most recent large U.S.-bound caravan in Guatemala earlier this week. “INCONSISTENCIES” Cienfuegos, a member of former President Enrique Pena Nieto’s government, was arrested in October at Los Angeles international airport and accused by U.S. prosecutors of collaborating with a splinter of a powerful drug cartel. He returned to Mexico in November after a federal judge granted a U.S. 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 the U.S. case was not strong enough to warrant charges against Cienfuegos, a decision Lopez Obrador publicly backed. Lopez Obrador said the hundreds of pages of evidence the DEA provided, 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 U.S. embassy in Mexico City referred a request for comment to the Department of Justice. A spokesman for the DEA, a division of Justice, did not immediately respond.