Motorists should be paying £1.10 a litre for unleaded petrol at the moment - and the only reason they are not is because retailers and refiners have accepted a drop in profits.
That's according to a survey by petrol-price analysis firm Catalist, which says that although petrol prices have risen 2.1p on average since July, the price of crude oil and the taxes on petrol have risen far more steeply than that.
A barrel of crude oil currently costs $95 (£45.50) in the United States, but was just $71 (£34.00) at the start of July.
In addition, the UK Government has raised taxes by more than 2p a litre in the same time period.
Catalist says that if petrol prices had risen at the same rate as crude oil prices and then had the extra tax added, the average price of a litre of unleaded would be £1.10 rather than 99p.
However, retailers and refiners are not expected to continue to absorb the price rises for long, sparking fears of a massive rise in inflation.
The price of a litre of unleaded is set to hit £1.02 a litre by the end of November, according to analysts.
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