Brent crude futures and WTI oil futures extended losses to around $3 a barrel as traders assess Middle East developments.
Iran warned it would retaliate beyond the Middle East if the US or Israel restart attacks on the Islamic Republic, following renewed threats from President Donald Trump.
The US and Iran seem deadlocked over how to turn their fragile ceasefire into a more permanent peace, with neither side toning down its belligerent rhetoric in recent days.
Trump said late Tuesday he might order a new round of strikes in the coming days as he tries to force Iran to make concessions over its nuclear program and reopen the Strait of Hormuz to lower energy prices.
“If aggression against Iran is repeated, the regional war that had been promised will this time extend beyond the region,” the Islamic Revolutionary Guard Corps said on Wednesday, according to the semi-official Tasnim news agency. The IRGC, which has gained even more influence over Iranian decision-making since the war erupted in late February, vowed “crushing blows in places you do not expect.”

