Ampol Ltd's stock plummeted 6.25% during intraday trading on Wednesday, significantly underperforming the broader market rally.

The sharp decline comes as fuel refiners face pressure from President Trump's announcement that he would suspend attacks on Iran for two weeks. The potential cease-fire raises the prospect of the Strait of Hormuz being unblocked, which would unwind the elevated refining margins that companies like Ampol had benefited from during the recent conflict.

The Iran conflict had previously boosted refining margins due to supply concerns, but the shift toward de-escalation now threatens to reverse those gains, leading to a sell-off in refining stocks despite overall risk-on sentiment in equity markets.