MEXICO CITY - Mexican President Claudia Sheinbaum on Wednesday expressed her disagreement with US President-elect Donald Trump's proposal to create an external revenue service agency to collect tariff income from trading partners.

Just days before Trump's Jan 20 inauguration, Sheinbaum said: "This is something that is not new. He has said it several times, and we... disagree, (but) we respect it."

"There will be time to be able to speak with President Trump's government" once he takes office, Sheinbaum said during her morning press conference.

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On Tuesday, Trump announced his plans to create an external service to collect tariffs, duties and all other foreign revenue to balance what he describes as the United States' unfair trade relationship with partners.

In response, Sheinbaum stressed that the trade agreement between Canada, the United States, and Mexico has greatly benefited the United States in terms of employment and production and has helped the region compete globally.

"In the case of the North American trade agreement, (between) Mexico, the United States and Canada, we really complement each other. And this region, to the extent that we continue together, will be able to compete better with other regions of the world," she said.

However, Mexico is prepared for potential policy changes, including Trump's threat to begin mass deportations of undocumented migrants, she said.

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"We champion the work of Mexicans in the United States, who contribute to the Mexican economy but contribute more to the United States economy. But, in the event of such a decision (mass deportation) by the United States government, we are prepared," said Sheinbaum.