Widespread reports of vehicles breaking down after motorists bought fuel from the forecourts of Tesco and Morrisons stores have left the supermarkets puzzled.

Thousands of motorists in London and the south east of England reported experiencing difficulties as their vehicles juddered, spluttered and lost power but both supermarkets say they have tested their fuel and cannot find a problem.

Preliminary investigations suggest that there are problems with a limited batch of fuel, possibly due to an excessive percentage of ethanol in the mix, which is believed to have been imported from a foreign refiner.

Trade associations which represent petrol retailers are advising motorists to continue to buy their fuel from their usual outlet.

Sam Bond

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