The BRICS summit in Rio de Janeiro hit a wall Monday morning when Donald Trump, now back in the White House, threatened to slap 10% tariffs on any country pushing what he called “anti-American” policies.

“Any Country aligning themselves with the Anti-American policies of BRICS, will be charged an ADDITIONAL 10% Tariff. There will be no exceptions to this policy,” Mr. Trump said in a Truth Social post. He did not elaborate, nor did he say what BRICS policies he was referring to.