South Korean stocks extended a historic selloff Wednesday, with Seoul's equity market shedding about $2.18 trillion in value over two sessions. The benchmark KOSPI .KS11 index plunged as much as 12.6 percent before closing down 6 percent, compounding Tuesday's near-11 percent rout that has erased almost 40 percent from a peak reached just over a month ago.

Finance Minister Koo Yun-cheol apologized to lawmakers for the introduction of single-stock leveraged ETFs, acknowledging they "had not been considered carefully enough." He joined the Bank of Korea governor and financial regulators late Wednesday to discuss emergency stabilisation measures, two weeks after announcing tighter regulations to cool the ETF investment boom.

The Ministry of Finance said it will immediately pursue further curbs on single-stock leveraged products, including individual investment limits — citing a cap of up to 20 percent of an investor's total amount — higher trading costs, and simulated trading requirements. It will also prepare a legal basis for emergency market-stabilisation steps.

Jon Withaar, senior portfolio manager at Pictet Asset Management, noted "definitely signs of panic and forced unwind in Asia technology today." Despite the collapse, the KOSPI remains up 41.5 percent in U.S. dollar terms year-to-date, making it the best-performing major market this year.