MEXICO CITY (Reuters) - Mexico's president on Friday said he was open to freeing drug lord Miguel Angel Felix Gallardo, jailed for the 1985 murder of a U.S. Drug Enforcement Administration (DEA) agent, on the basis of old age and poor health.

       A legendary figure in the drug world and co-founder of the Guadelajara cartel, Felix Gallardo was a pioneer in trafficking large shipments of cocaine to the United States in alliance with the deceased Colombian drug lord Pablo Escobar.

       But his empire crumbled after the murder of Enrique "Kiki" Camarena, an undercover DEA agent behind a string of successful drug busts. Camarena's killing triggered a large DEA investigation and damaged U.S.-Mexico ties.

       In a prison interview aired this week by NBC News, a frail-looking Felix Gallardo, 75, praised leftist President Andres Manuel Lopez Obrador "as a man of goodwill" and commended him for fighting social injustice.

       When asked about the interview, and if he was open to granting Felix Gallardo a pardon under a proposed new law that would free thousands of prisoners, Lopez Obrador said: "If it is justified ... of course, yes."

       "I also want him to understand my situation, that I do not want anyone to suffer. I do not want anyone to be in jail. I am a humanist," said Lopez Obrador, adding that prosecutors would review the case.

       The Mexican leader last month proposed the release of thousands of inmates who were elderly, victims of torture or suffered from health problems, as well as those who committed non-serious crimes.

       Felix Gallardo, a former police officer who was jailed in 1989 with two other close allies for masterminding Camarena's murder, is blind in one eye, deaf in his left ear and could not walk, NBC News reported.

       The U.S. Embassy was not immediately available for comment.

       (Reporting by Raul Cortes; Writing by Drazen Jorgic; Editing by Cynthia Osterman)