The S&P 500 and the Nasdaq fell, with technology stocks leading declines, as investors steered clear of risk-laden assets on worries the Trump administration's upcoming tariff plans will hurt economic growth.
Global stocks tumbled, gold prices scaled new highs and US government bonds climbed after US President Donald Trump said on Sunday that reciprocal tariffs he is set to announce on Wednesday will include all nations.
He has already imposed tariffs on aluminum, steel and autos, along with increased tariffs on goods from China.
European shares fell to their lowest close in two months, while the FTSE 100 hit a one-month low.
"There's a lot of uncertainty related to (Trump's) announcement," said Mark Luschini, chief investment strategist at Janney Montgomery Scott in Philadelphia.
"Many industries have begun to feel the impact of the tariffs that have been announced and are making assumptions about what's likely to follow. That is driving expectations economic data will continue to be somewhat weak and prices may very well be moving higher."
US stock markets have sold off this year as the Trump administration's tariff policies raised fears of a global trade war that would hurt economic growth and spur inflation.
The three major US indexes are on track for sharp monthly and quarterly losses, with the S&P 500 and the tech-centric Nasdaq poised for their steepest quarterly drops in three years.
Tech stocks were the worst hit, with Nvidia falling 3.9% and Microsoft down 2.2% as investors worried about companies' AI spending plans.
Tesla fell 4% after Stifel lowered the electric-vehicle maker's delivery forecast ahead of Wednesday's first-quarter report.
As a result of tariff uncertainties, Goldman Sachs raised the probability of a US recession to 35% from 20%, cut its year-end target for the S&P 500 to 5,700 and forecast more interest rate cuts by the Federal Reserve.
Focus this week will also be on economic data including ISM business activity surveys and the crucial non-farm payrolls report. Also due this week are speeches from several US central bank officials including Fed Chair Jerome Powell.
