(Bloomberg) -- In a dramatic market shift, copper prices have fallen below $9,000 per ton, marking the largest decline since March 2020. This significant drop has raised alarm among traders and investors, driven primarily by escalating concerns surrounding an intensifying trade war between the United States and China, which has triggered a massive selloff in both metals and mining equities.

On Friday, copper experienced a steep decline, plummeting as much as 6.8% to reach $8,734 per ton in London. This drop was part of a broader trend that saw losses accelerating across the industrial metals markets, following a heavy selloff the previous day. Trading on New York’s Comex also reflected this downturn, indicating that copper was on a trajectory toward its largest two-day decline since 2011.

The catalyst for this market upheaval came from a report by China’s official Xinhua News Agency, which announced that Beijing would retaliate against U.S. tariffs by imposing a substantial 34% duty on all imports from the United States, effective April 10. This move has had a cascading effect on major mining companies, with stocks like Glencore Plc, Teck Resources Ltd., and Antofagasta Plc witnessing declines of over 10% as investors reacted to the news.

This reversal has been particularly jolting for copper traders, who had previously focused on the optimistic supply-side impacts resulting from a global push to export copper to the U.S. ahead of expected tariffs. However, with the implementation of President Trump’s trade barriers now imminent, market attention has quickly shifted to the potential fallout on demand, not only in the U.S. but also across the globe.

Goldman Sachs Group Inc. recently issued a report that underlined the complexities of the current market dynamics, stating, “While we remain structurally bullish on copper in the long run, weaker global GDP and slowing copper demand growth pose risks that could delay the deficit we expect to see in the market this year.” This sentiment reflects a cautious outlook among analysts as they reassess the balance between supply and demand in light of new economic realities.

As of 4:36 p.m. local time, copper trading on the London Metal Exchange was recorded at $8,804.50 per ton, marking a potential 10% drop for the week—the most significant decline since the pandemic-induced market turmoil began in March 2020. Aside from copper, other metals also faced grim prospects; aluminum saw its prices decrease for the twelfth consecutive day, while zinc, lead, and nickel also suffered severe losses throughout the week. Tin, after a brief rally, experienced a sharp decline on Friday, erasing earlier weekly gains amid concerns over supply disruptions. Notably, Chinese markets were closed on Friday due to a public holiday, further complicating the situation.

--With assistance from Atul Prakash.

©2025 Bloomberg L.P.