In a flurry of early Monday social media posts, US President Donald Trump took aim at “biggest abuser” China for striking back against his hefty new tariffs, brushed off global market jitters, voiced confidence in the US economy, and told Americans not to be “stupid” or “weak”.

Trump stood firm on the steep “reciprocal” tariffs he imposed on all imports entering the US, set to take effect on Wednesday, including a 34 per cent duty on Chinese goods. In response, Beijing imposed its own 34 per cent tariffs on US products.

“The fact that the biggest abuser of them all, China, whose markets are crashing, just raised its Tariffs by 34%, on top of its long term ridiculously high Tariffs (Plus!), not acknowledging my warning for abusing countries not to retaliate,” he posted to his Truth Social account.

On their opening Monday, US markets continued a sell-off from last week, with the Dow Jones Industrial, S&P 500 and Nasdaq indexes all dropping another 4 per cent or more. Stocks then mounted a short-lived rally that took the Dow into positive territory before falling into the red again.

Earlier, Hong Kong’s Hang Seng plunged by 13.2 per cent, Taiwan’s index fell by 10 per cent, and mainland China’s key indexes down as much as 9 per cent. Japan’s Nikkei dropped 8 per cent, while in Europe, France’s CAC 40, Germany’s DAX, and Britain’s FTSE 100 all fell by 4 to 6 per cent.

India’s stocks saw their biggest drop since March 2020, and Middle Eastern markets tumbled, with Brent crude down nearly 15 per cent.