First Thing: Markets plunge as IMF says Trump trade war poses ‘significant risk’ to global economy

London's stock market opened at its lowest level since January, while France suggests pause on investing in the US. Plus, what now for TikTok?

Good morning.

Donald Trump's barrage of tariff announcements has wiped trillions of dollars off the value of the world's largest companies and supercharged recession fears, with London's stock market opening on Friday morning at its lowest level since January.

What has the political reaction been? There are some signs of a slight Republican backlash, with the former Senate majority leader Mitch McConnell calling tariffs bad policy" that hurt ordinary Americans. McConnell and three other Republican senators backed a Democrat resolution demanding that the 25% tariffs on Canadian products be reversed.

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Were others fired? Yes - Trump said earlier on Thursday that he had fired some" White House national security council officials. The announcement came a day after the far-right activist Laura Loomer raised concerns with him about staff loyalty.