Malaysian shares erased an opening rally to end in the red on Wednesday, weighed down by geopolitical uncertainty over the U.S.-Iran ceasefire timeline.

The FTSE Bursa Malaysia KLCI shed 4.70 points to end 0.3% lower at 1,683.42. The day range was between 1,680.46 and 1,695.68.

In local news, Malaysia has warned that the economic impact of the Iran-linked energy crisis will intensify from June, as fiscal buffers from subsidies and domestic gas output will begin to fade, South China Morning Post reported, citing Economy Minister Akmal Nasrullah Mohd Nasir.

Malaysia has overtaken the US as a key supplier of chipmaking equipment to China, signalling a shift in regional trade flows. Imports from Malaysia more than doubled to $3.4 billion in 2025, underscoring its rising importance in the semiconductor supply chain.

In economic news, the International Monetary Fund has lowered its growth estimates for most Asian economies for 2026, according to a recent release. Cumulative growth among Southeast Asia's five biggest economies, including Indonesia, Malaysia, the Philippines, Singapore, and Thailand, will fall to 3.7% in 2026 from 4.9%, although this will recover to 4.7% next year, the organization said.

In corporate news, shares of Muhibbah Engineering (M) (KLSE:MUHIBAH) gained 2% on Wednesday's close after it bagged a contract worth about 120 million ringgit for works on the Penang Light Rail Transit (LRT) Mutiara Line project.