Global investors are fleeing Mexico’s financial markets, sending the peso to record lows on mounting concerns that Donald Trump’s trade policy could end the country’s privileged status among developing countries.

The peso on Wednesday tumbled to another all-time low against the dollar as Mr. Trump pledged to change U.S. trade policy with Mexico. “Mexico has taken advantage of the United States,” he said during his press conference. “It’s not going to happen anymore.”

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