Pump probe hits BP and Shell

Oil giants BP and Shell are to figure in a massive US government probe of petrol prices, aimed at rooting out unfair practices in the industry.

The investigation is being launched by the Federal Trade Commission (FTC) and is the biggest of its kind. It will collect information from 80,000 petrol stations throughout the US – almost 40 per cent of the national total – and will cover the 360 biggest cities. Under scrutiny will be petrol stations owned by all the large operators, including branches from both Shell and BP's retail networks. Other subjects of the investigation include ExxonMobil and ChevronTexaco.

Sources at the UK's Office of Fair Trading have indicated that they will be "very interested" to hear the results of the US investigation, as many of its findings will likely reflect on the state of the market on this side of the Atlantic.

The probe is being organised to answer a number of pressing questions about the state of petrol retailing. The FTC is particularly keen to find out why petrol prices are often subject to sudden jumps, and has said it will be on the lookout for any signs of price collusion between the major players.

The FTC will also be examining the delays in passing crude price movements on to customers, particularly when oil prices are falling. "We will be looking for the 'rocket and feathers' effect," said an FTC spokesman, "where the oil companies shoot the petrol prices up when crude is rising, but only let them fall back down very slowly."