Our local Tesco has dropped the price 2p per litre of diesel - we only have Sainsbury as supermarket competition. If they can drop the price by 4 or 5 pence in certain stores they should be forced to drop their price, no matter what the commodity is - be it petrol or groceries, it should be the same price drop throughout the country. Cartel operating is obvious with the large supermarkets and the powers that be are too b****y lazy to do any thing about it. The services on the M4 at Sarn Park (Junction 36) Sheel fuel, were lower than Tesco until last night - do not know what their price is now.