US President Donald Trump said he would fire the head of the agency charged with publishing some of America's most closely watched economic data, after a weaker-than-expected jobs report stoked further alarm about his tariff policies.

His decision to move forward with plans to sharply raise tariffs on goods from countries around the world had already sent financial markets in the US shuddering.

In the US, the three major indexes dropped, with the S&P falling 1.9% by mid-afternoon.

That followed earlier sell-offs in Europe and Asia, as investors dumped shares of firms such as South Korean steel manufacturers and German truck-maker Daimler.

Trump's plans leave most goods coming into the US facing new taxes of 10% to 50%, depending on their origin, and will lift tariff rates in the US to the highest levels in nearly a century.