Sir Keir Starmer said he would consider all options to address the looming cost-of-living crisis as a result of the Iran war.
The Prime Minister said a meeting of the emergency Cobra committee would examine “every lever that’s available to Government” to respond to soaring energy prices as a result of the conflict.
The meeting comes as Donald Trump’s deadline looms for Iran to reopen the Strait of Hormuz, a major oil and gas shipping route, or face the obliteration of its power plants.
Mr Trump’s 48-hour ultimatum expires at 11.45pm.
Financial markets in Europe and Asia fell and oil prices rose as the crisis threatened to escalate.
Oil benchmark Brent crude lifted 1% to nearly 114 US dollars a barrel after Iran warned it will strike electrical plants across the Middle East if Mr Trump follows through on his threat to bomb power stations in the Islamic Republic.
Sir Keir told reporters: “Cobra is the opportunity at the highest level to bring people together on matters of real, significant national importance.
“Obviously Cobras are usually used for military considerations, consular considerations, but I think with the Iran war, most people are very concerned now, not only what they’re seeing on their screens in relation to the conflict itself, but also that question of: ‘How is it going to affect me and my family?’
“And so today we’re looking at the economic impact, and I am asking for every lever that’s available to the Government to deal with the cost of living to be discussed at Cobra.
“Hence we’ve got the Bank of England and others there.
“But I want to make sure that when it comes to the cost of living, we’re doing everything we possibly can at a very difficult period like this.”
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