London (CNN Business) 1. Tariff Man: A tariff threat from President Donald Trump is roiling markets again.

US stock futures and global stock markets, including shares of Asian and European automakers, tumbled Friday after President Donald Trump said the United States will impose a 5% tariff on all Mexican imports.

Stock futures indicated that those losses would extend to the United States. The Dow is poised to fall 260 points, or 1%, when markets open. The S&P 500 is tracking similar losses, while the Nasdaq could drop 1.3%.

The Mexican peso is down more than 3% against the US dollar.

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