Oil prices lifted back above a key level yesterday after an explosion at one of BP's refineries in the United States.
The price of US light crude topped $60 US dollars a barrel following the blast at the company's Texas City plant on Thursday night.
It is the second explosion to hit the Texas refinery since March, when a blast killed 15 people.
It also comes only weeks after a hurricane apparently damaged one of BP's new oil platforms in the Gulf of Mexico.
Crude prices and BP's shares rose as the blast and a blaze at another oil firm's refinery in Louisiana fanned fears that production may not be able to meet US demand in coming months, analysts said.
No injuries were reported in the latest explosion at the Texas City refinery, although a unit used to remove sulphur from heavy crude oil caught fire.
A BP spokesman said that firefighters had put out the blaze, but it was too early to say what caused it. He said all BP employees had been accounted for.
The March 23 blast, which occurred in a unit that boosts the octane level of petrol, killed 15 contractors and injured more than 170 workers.
Texas City, one of five BP refineries in the US, processes 433,000 barrels of crude oil a day and three per cent of the United States' petrol.
"We are talking about a minimal impact on production output of petrol," the spokesman said. The explosion came hours after a fire at Murphy Oil Corporation's 120,000-barrel-a-day Louisiana diesel hydrotreater, which also removes sulphur from fuel.
Supply outages, such as refinery blackouts and weather-related shutdowns, have factored into the upward movement of the price of crude in 2004 and much of this year.
Oil prices are now more than 40 per cent higher from a year ago, but would need to reach $90 a barrel to match the all-time, inflation-adjusted high set in 1980.