Jakarta (ANTARA) – Indonesia’s benchmark stock index suffered a sharp sell-off on Thursday, dragged down by heavy losses in the materials and energy sectors.The Jakarta Composite Index (JCI) closed down 223.56 points, or 3.54 percent, at 6.094.94. Meanwhile, the blue-chip LQ45 index fell 14.28 points, or 2.26 percent, to settle at 616.40.Market sentiment turned sharply bearish following details of an upcoming government regulation regarding natural resource export management, an analyst said.The policy will appoint state-owned enterprises (SOEs) as sole exporters for key commodities, including crude palm oil (CPO), coal, and ferroalloys.”The primary driver behind the JCI's decline is the planned centralization of commodity exports under state entities, which investors believe will erode the profitability of private companies and hurt shareholders,” Lionel Priyadi, Fixed Income and Macro Strategist at PT Mega Capital Indonesia, said on Thursday.”We are seeing strong negative reactions from both domestic and foreign investors.”Traders are specifically reacting to the establishment of PT Danantara Sumberdaya Indonesia (DSI), a specialized state-owned export entity.Operating directly under the Danantara Investment Management Agency (BPI Danantara), DSI’s mandate is to tighten control over strategic resources.The government justified the intervention by citing alleged historic export under-invoicing, which it claims has cost the state roughly Rp15,400 trillion (US$872 billion) over the last 34 years.The JCI opened lower and remained firmly in negative territory throughout both trading sessions.All 11 sector indices on the Indonesia Stock Exchange recorded losses.The basic materials sector plummeted the most, dropping 6.96 percent, followed closely by the energy sector down 6.74 percent, and consumer cyclicals, which shed 5.70 percent.Market turnover reached 35.77 billion shares valued at Rp18.49 trillion across more than 2.1 million transactions.Market breadth was overwhelmingly negative, with 663 declining stocks against just 88 gainers, while 69 remained unchanged.Regionally, Asian markets closed mixed on Thursday.Japan’s Nikkei surged 3.10 percent to 61,658.00 and Singapore’s Straits Times Index ticked up 0.02 percent.However, China's markets mirrored Jakarta's anxieties, with the Shanghai Composite sliding 2.04 percent to 4,007.28, and Hong Kong’s Hang Seng Index dropping 1.03 percent to 25,386.52.