Mexican President Claudia Sheinbaum said on Thursday that she will propose constitutional reforms aimed at protecting the country’s sovereignty over concerns the U.S. military could cross the border to pursue Mexican drug cartels.

Sheinbaum made the remarks after the Trump administration designated six Mexican drug cartels as foreign terrorist organizations, stoking fears that President Donald Trump may be setting up the possibility for U.S. military action inside Mexico.

“The Mexican people will not accept under any circumstances interventions, interference or any other act from abroad that could be harmful to the integrity, independence and sovereignty of the nation,” Sheinbaum said.

The Mexican cartels on the Trump administration’s list include the Sinaloa, Jalisco, Zetas, the Gulf Cartels, Cartel Unidos and “La Nueva Familia Michoacana.” Other groups include the international Venezuelan gang Tren de Aragua and the Salvadoran gang Mara Salvatrucha – also known as MS-13.

“What we want to make clear in the face of this designation is that we do not negotiate sovereignty,” Sheinbaum said. “This cannot be an opportunity for the United States to invade our sovereignty.”

Sheinbaum also proposed a second reform to the constitution to create harsher penalties for Mexican nationals and foreigners involved in gun trafficking.

Mexico has long demanded that the U.S. do more to prevent guns from being smuggled into Mexico from the U.S.

The Associated Press and Reuters contributed to this report.