The RAC is warning drivers are being overcharged £5 every time they fill up their cars, as retailers fail to pass on savings to their customers.
Prices soared last year in the wake of Russia's invasion of Ukraine, though have been slowly falling amid government threats for retailers to pass savings on to consumers.
Brent crude oil topped $110 a barrel last summer, but prices have since settled in recent weeks below $80 a barrel, albeit the conflict in the Middle East saw prices soar above $90 a barrel last month.
Despite prices slowly on their way down, the RAC said drivers are still paying around a fiver more than they should be to fill up an average 55-litre family car at £80.62, with diesel car owners overpaying by £2.50 at £84.92
The RAC believes petrol should be sold for an average of 137p and diesel for 150p, based on retailers taking a fairer margin.
In October, Claire Coutinho wrote to industry executives warning them she would "not hesitate to call out retailers who rip off the public".
Simon Williams of the RAC said: “The biggest retailers don’t seem to have heeded the warnings levelled at them.
“While the Energy Secretary’s action may have encouraged retailers to begin reducing their prices, it’s undoubtedly a case of far too little, far too late.”
The UK's flagship share index, the FTSE100, was x xx-points at xx shortly after opening this morning.
Meanwhile, Brent crude futures were down 0.90% at $78.17 a barrel this morning.
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