Zinc prices traded below $3,900 per tonne after retreating sharply from a high reached more than four years ago, as a sentiment-driven selloff swept through base metals. The decline followed a report that the White House was hesitating over import tariffs on refined copper, leading traders to unwind bullish positions and lock in profits. Higher bets on a Federal Reserve rate hike next month strengthened the U.S. dollar, making dollar-denominated metals less attractive, while the prospect of greater Chinese export deliveries to the London Metal Exchange eased some supply concerns. Zinc had surged in recent months amid tightening supply, including disruptions at several mines in China and restrictions on Iranian ore shipments linked to Middle East tensions. LME warehouse inventories remain low by historical standards, physical availability is particularly tight outside China, and sharply lower smelter treatment charges point to continued concentrate-market tightness.