MEXICO CITY - Mexican President Claudia Sheinbaum on Thursday rejected claims that US agents are involved in anti-drug trafficking operations on Mexican soil.

The denial followed a front-page report earlier in the day by a Mexican media outlet, which published a photograph allegedly showing US Immigration and Customs Enforcement agents participating in an operation in Sinaloa state, aimed at dismantling clandestine drug laboratories.

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Sheinbaum dismissed the report as "fake" news, saying that since the previous administration, "there has been no subordination or participation of members of any US agency in any operation" within Mexico.

The government is investigating the origin of the photograph and whether it was taken in Mexico or elsewhere, she said.

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Mexico no longer permits the United States to dictate its policies, Sheinbaum said. "We are not going to allow the violation of our sovereignty ... it is a respectful relationship that has been maintained until now with (US) President (Donald) Trump."

"It is important for the people of Mexico always to know this, and that under no circumstances will interference or violation of our sovereignty be allowed," she said.