Australia's consumer watchdog will haul in major fuel suppliers for an explanation on skyrocketing prices.
A number of retailers including Ampol, BP, Chevron, Exxon Mobil and 7-Eleven will be among the companies summoned by the Australian Competition and Consumer Commission for an emergency meeting.
Iran has closed one of the world's most important oil corridors, the Strait of Hormuz, in response to the US-Israel war on the country.
This has led to a spike in oil prices, sending unleaded petrol in Australia's major cities above $2.20 a litre, and diesel to more than $2.60 a litre.
Treasurer Jim Chalmers said the steep increases in petrol prices after war in the Middle East broke out had raised serious concerns at the ACCC.
"The ACCC are hauling the petrol suppliers and retailers in for an explanation," he said.
"I’ve made it very clear that if they find evidence of misconduct, we expect the ACCC to throw the book at them."
Labor has previously asked the consumer watchdog to monitor prices after war erupted to ensure motorists weren't taken for "mugs".
Energy Minister Chris Bowen said fuel standards will be relaxed for two months to allow more supply to combat shortages at the bowser.
This will bring an extra 100 million litres a month, the equivalent of about two days' worth of supply.
Motoring groups and the federal government have urged Australians to stop panic buying and stockpiling fuel, reassuring the community fuel was still arriving into the country.
One Nation MP Barnaby Joyce has suggested reserving fuel for farmers and regional areas by introducing rationing for the cities as the war drags on.
Fuel transport companies have thrown their support behind the proposal.
But the NRMA has opposed the idea, saying rations would cause unnecessary economic and social impacts.
Opposition Leader Angus Taylor said the government needed to acknowledge there was a problem with fuel supply.
"What's needed is to move the fuel through the supply chain as quick as possible," he told Nine's Today on Tuesday.
"We've got a refinery exporting its fuel ... that fuel needs to go to Australians."
Finance Minister Katy Gallagher said it was the government's responsibility to think through contingencies and be ready to respond to issues as a result of the war.
"Every lever that we've got available is being utilised, and we will continue to do that as the conflict continues," she told ABC News Breakfast.
