Motorists face yet another rise in petrol prices following renewed tension in the Middle East, it was revealed today.

Petrol prices could surge by another 5p per gallon, or 1p per litre, in the coming weeks after an increase in the cost of crude oil.

Oil prices in London climbed to a six-month high yesterday amid fears of escalating violence in Israel.

Iran and Iraq fuelled concern by refusing to rule out the use of oil supplies as a weapon against the United States.

By early yesterday afternoon, oil for delivery in May was 26.60 US dollars (£18.48) a barrel on London's International Petroleum Exchange.

Kamal Sharma, currency strategist at Commerzbank, said there was now increased pressure on oil giants and supermarkets to reflect the increase on the forecourt.

"I think you have to say the chances of petrol prices going up are quite real," he said.