MEXICO CITY (AP) — President Claudia Sheinbaum suggested Tuesday that Mexico could retaliate with tariffs of its own, after U.S. President-elect Donald Trump threatened to impose 25% tariffs on Mexican goods if the country doesn't stop the flow of drugs and migrants across the border.

Sheinbaum said she was willing to engage in talks on the issues, but said drugs were a U.S. problem.

"One tariff would be followed by another in response, and so on until we put at risk common businesses," Sheinbaum said, referring to U.S. automakers that have plants on both sides of the border.

She said Tuesday that Mexico had done a lot to stem the flow of migrants, noting "caravans of migrants no longer reach the border." She also said Mexico had worked to stem the flow of drugs, like the deadly synthetic opioid fentanyl, even though "it is a problem of public health and consumption in your country's society."

Sheinbaum also criticized U.S. spending on weapons, saying the money should instead be spent regionally to address the problem of migration. "If a percentage of what the United States spends on war were dedicated to peace and development, that would address the underlying causes of migration," she said.

Sheinbaum's bristly response suggests that Trump faces a much different Mexican president than he did in his first term.

Back in late 2018, former President Andrés Manuel López Obrador was a charismatic, old-school politician who developed a chummy relationship with Trump. The two were eventually able to strike a deal in which Mexico helped keep migrants away from the border — and received other countries' deported migrants — and Trump backed down on the threats.

But Sheinbaum, who took office Oct. 1, is a stern leftist ideologue trained in radical student protest movements, and appears less willing to pacify or mollify Trump.

However, it's not clear how serious Trump's threat is. The U.S.-Mexico-Canada free trade agreement forbids just imposing tariffs on other member countries. And it's not clear whether the economy could even tolerate sudden levies on imports: Auto plants on both sides of the border rely on each other for parts and components; some production lines could screech to a halt.

"It is unacceptable and would cause inflation and job losses in Mexico and the United States," Sheinbaum said.