The cost of a fill-up hit £100 today as pump prices soared again thanks to the Iran war dragging on. Average petrol prices hit a new post-war record while diesel also soared, meaning filling up the average family car with the fuels hit £89 and £100 respectively. In turn, oil prices have shot up and sent pump prices soaring. Average petrol pump prices hit 161.47p a litre today - the highest since the start of the Iran war – while diesel hit 181.45p. Treasury sources said a decision on Fuel Duty would not be made until Mr Healey's first Budget, on October 28.