US stock markets tumbled on Thursday as investors parsed the sweeping change in global trading following Donald Trump’s announcement of a barrage of tariffs on the country’s trading partners.

All three major US stock markets closed down in their worst day since June 2020, during the Covid pandemic. The tech-heavy Nasdaq fell 6%, while the S&P 500 and the Dow dropped 4.8% and 3.9%, respectively. Apple and Nvidia, two of the US’s largest companies by market value, had lost a combined $470bn in value by midday.

Meanwhile, the US dollar hit a six-month low, going down at least 2.2% on Thursday morning compared with other major currencies and oil prices sank on fears of a global slowdown.