Jakarta. Indonesia's stock market suffered a nearly 5% rout on Wednesday as the rupiah sank to a fresh record low against the US dollar, triggering a broad-based selloff across equities.

Jakarta Composite Index (JCI) tumbled 305 points, or nearly 5%, to 5,889 in intraday trading, extending losses as investors reacted to mounting pressure on the rupiah and growing external uncertainties.

Data from RTI showed trading volume reached 26.3 billion shares, with turnover totaling Rp 14.9 trillion ($831 million) across more than 1.7 million transactions. Market breadth was overwhelmingly negative, with only 35 stocks advancing against 714 decliners, while 64 stocks were unchanged.

The selloff came as the rupiah weakened 0.39% to Rp 17,900 per US dollar at 9:26 a.m. Jakarta time on Wednesday. According to BRI Danareksa Sekuritas, the level marked a new all-time low for the Indonesian currency and brought it closer to the psychologically important Rp 18,000 threshold.

BRI Danareksa Sekuritas attributed the pressure partly to persistent geopolitical tensions in the Middle East, which have boosted demand for safe-haven assets, particularly the US dollar.

"The US Dollar Index (DXY) strengthened after US labor market data showed the economy remains resilient. Market expectations for Federal Reserve rate cuts have diminished, keeping the US dollar strong," the brokerage said.

On the domestic front, BRI Danareksa noted that demand for foreign exchange typically rises in the second quarter as companies make interest and principal payments on external debt and repatriate investments.

The brokerage also pointed to Indonesia's shrinking trade surplus as imports continue to increase amid the government's pro-growth economic policies.

In addition, investors are closely monitoring global geopolitical developments and the potential impact of the FTSE Russell rebalancing scheduled for the end of June, which could trigger further portfolio adjustments in the domestic market.