LONDON (Reuters) - Britain's consumer affairs watchdog said competition in the UK petrol and diesel market was "working well" and there was little evidence that pump prices rise quickly when the wholesale price goes up but fall more slowly when it drops.
The Office of Fair Trading (OFT) said on Wednesday that rises in pump prices for petrol and diesel over the last decade had been caused largely by higher crude oil prices and increases in tax and duty, and not a lack of competition.
"The evidence gathered by the OFT suggests that at national level competition is working well in the UK road fuel sector," the OFT report said, adding that it found "very limited evidence ... that pump prices rise quickly when the wholesale price goes up but fall more slowly when it drops."
The OFT last year launched a fact-finding exercise, seeking information from industry and consumer groups on whether prices paid at the pump were a fair reflection of underlying costs.
Leading petrol retailers in Britain include BP, ExxonMobil, and Shell, as well as supermarkets like Tesco, Asda, Sainsbury's and Morrisons.
The OFT said Britain had some of the cheapest road fuel prices in Europe, noting that in the 10 years to 2012 pump prices increased from 76 pence per litre (ppl) to 136 ppl for petrol, and from 78 ppl to 142 ppl for diesel, caused largely by an increase of nearly 24 ppl in tax and duty and 33 ppl in the cost of crude oil.
The watchdog, however, did identify a lack of pricing information on motorways as a concern and said it would not rule out taking action in some local markets if there was "persuasive evidence" of anti-competitive behaviour.
Angus Elphinstone, founder of delivery website Anyvan, said the OFT's investigation would leave British motorists and businesses "with the feeling that they've been short-changed yet again"