MEXICO CITY, Mexico (AFP) — Mexico’s president warned the United States (US) Thursday her country would never tolerate an “invasion” of its national sovereignty and vowed fresh legal action against its gunmakers after Washington designated cartels as terrorist organisations.

The remarks were the latest in a series hitting back at the administration of US President Donald Trump, which has ramped up pressure on its southern neighbour to curb illegal flows of drugs and migrants.

Mexico is trying to avoid the sweeping 25 per cent tariffs threatened by Trump by increasing cooperation in the fight against narcotics trafficked by the cartels in his sights.

The eight Latin American drug trafficking groups designated as terrorist organisations include Mexican gangs such as the Jalisco New Generation and Sinaloa cartels — two of the country’s most powerful and ultra-violent criminal organisations.

“This cannot be an opportunity for the US to invade our sovereignty,” President Claudia Sheinbaum told a news conference.

“They can call them (the cartels) whatever they want, but with Mexico, it is collaboration and coordination, never subordination or interventionism, and even less invasion.”

Sheinbaum said Mexico would expand its legal action against US gun manufacturers, which her government accuses of negligence in the sale of weapons that end up in the hands of drug traffickers.

The lawsuit could lead to a new charge of alleged “complicity” with terrorist groups, she said.

Trump signed an executive order on his first day back in the White House last month saying that the cartels “constitute a national-security threat beyond that posed by traditional organised crime”.

US Secretary of State Marco Rubio said Thursday that the designations “provide law enforcement additional tools to stop these groups”.

“Terrorist designations play a critical role in our fight against terrorism and are an effective way to curtail support for terrorist activities,” he said in a statement.

While he did not mention it, the move has raised speculation about possible military action against the cartels.

Tech billionaire Elon Musk, who has been given a prominent role in the Trump administration, suggested the designation “means they’re eligible for drone strikes”.

On Wednesday, Sheinbaum confirmed that the United States had been operating drones spying on Mexican cartels as part of a collaboration that has existed for years between the two countries.

According to The New York Times, Washington has stepped up secret drone flights over Mexico in search of fentanyl labs as part of Trump’s campaign against drug cartels.

The CIA has not been authorized to use the drones to take lethal action and any information collected is passed to Mexican officials, the Times said, adding that the covert program began under Trump’s predecessor Joe Biden but had not been previously disclosed.

Military threats from the United States always generate resentment in Mexico, which lost half of its territory to the United States in the 19th century.

Sheinbaum said that she would present to Congress a constitutional reform to protect the country against possible actions “that are harmful to the integrity, independence and sovereignty of the nation” or the violation of its territory.

Mexico says that between 200,000 and 750,000 weapons manufactured by US gunmakers are smuggled across the border from the United States every year, often being used in crime.

The Latin American country tightly controls firearm sales, making them practically impossible to obtain legally.

Even so, drug-related violence has seen around 480,000 people killed in Mexico since the government deployed the army to combat trafficking in 2006, according to official figures.