An ex-associate of Joaquín ‘El Chapo’ Guzmán has testified that the accused drug lord once paid a US$100-million bribe to former a Mexican president.

Alex Cifuentes, who has described himself as Guzman’s onetime right-hand man, discussed the alleged bribe under cross-examination in US federal court.

When asked if he told authorities in 2016 that Guzman arranged the bribe, he answered, “That’s right.”

But former president Enrique Peña Nieto has denied taking bribes.

The allegations are among the most explosive to emerge from Guzman’s trial, which began in November and has so far featured testimony of lower-level corruption.

Guzman, 61, was extradited to the United States in 2017 to face charges of trafficking cocaine, heroin and other drugs into the country as leader of the Sinaloa Cartel.

Cifuentes testified he had told US prosecutors that Peña Nieto initially reached out to Guzman, asking for $US250 million.

Cifuentes is one of about a dozen witnesses who have so far testified against Guzman after striking deals with US prosecutors.

The trial has provided a window into the secretive world of the Sinaloa Cartel, one of the world’s most powerful drug trafficking organisations.

Author of The Last Narco Malcolm Beth tells Ross Greenwood “it was a bombshell”.

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