Shares in BP PLC (LSE:BP.), Shell PLC (LSE:SHEL, NYSE:SHEL) and Centrica PLC (LSE:CNA) were leading the small band of FTSE 100 risers on Thursday, as oil and gas prices rose after Donald Trump said the US "will hit Iran extremely hard" over the next few weeks to bring the war to an end.
Brent crude oil climbed back up 6.5% to $107.75 a barrel, with US West Texas Intermediate rising 6.2% to $106.32 a barrel.
UK natural gas prices rose 4% to 125.3p a therm, with European prices up a similar degree to €49.5 a megawatt-hour.
BPO shares climbed 3.7%, Shell 2.6% and British Gas owner Centrica 1.7%. On the FTSE 250, Ithaca Energy PLC (LSE:ITH) and Harbour Energy PLC (LSE:HBR) gained 3.5% and 2.3%.
President Trump declared in a national address that the core strategic objectives in Iran were "nearing completion", expecting US forces would "finish the job" within "two to three weeks".
He added: "We are going to hit them extremely hard over the next two or three weeks. We are going to bring them back to the Stone Ages where they belong" unless the Strait of Hormuz is reopened.
Trump reiterated his claim that Iran has sought a ceasefire and that talks were "going very well", though Tehran’s foreign ministry called the assertion "false and baseless".
The US President said the US is "better prepared" than ever to deal with the economic ramifications of the war, with US and Venezuela's oil production meaning the US does not need oil from elsewhere.
"To those countries that can’t get fuel, many of which refuse to get involved in the decapitation of Iran," he said, "build up some delayed courage, go to the Strait and just take it. Protect it."
The expected chances of the Strait opening by the end of April fell to 13% on prediction market Polymarket, down from 24% the day before and above 30% at the end of last week.