The cost of fuel remains at "rip-off levels" despite a crash in the price of oil, a campaigner has claimed.
Howard Cox, founder of FairFuelUK, said the average prices for litres of petrol and diesel should be 98p and 106p respectively, but they are around 10p higher.
Mr Cox claimed that even before Monday's oil price collapse, the UK's fuel supply chain had "dishonestly held back" falls in wholesale costs which took place last month.
He said: "Even with 70% less fuel being sold, the dishonesty from these faceless businesses, using the coronavirus crisis as a smokescreen to maintain their profits, beggars belief.
"It's time the Government really looked after the highest taxed drivers in the world and our vital haulage industry, and introduce PumpWatch as a matter of emergency.
"An independent pricing watchdog is vital to protect our economy and allow essential workers to fill up their vehicles with the fairest and most honest prices at the pumps."
On Monday, traders were being paid more than 40 dollars to buy a barrel of West Texas Intermediate, the benchmark for US oil, partly due to a quirk of the market as falling global demand pushed the price into negative territory for the first time in history.
Oil falls 37% today – biggest drop since 1982 – because there's nowhere to store it and nobody to use it. Barrel of WTI Crude now $10 – that's less than a couple of coffees and a cake. Let's see how quickly petrol and diesel come down? Don't hold your breath.
— Quentin Willson (@QuentinWillson) April 20, 2020
They were keen to offload their barrels to avoid being obliged to take delivery when the deadline for May contracts expired on Tuesday.
Normally traders have no problem selling their contracts to a refinery, or other business that wants oil.
But international demand has dropped significantly in recent weeks, while Saudi Arabia ramped up production after a falling out with Russia.
Although Saudi Arabia and the rest of oil producing cartel Opec has now committed to slashing production again, these cuts have yet to make an impact on a market flooded by oil.
However, the collapse is unlikely to lead directly to significant discounts for drivers at the pumps. The price of Brent crude to be delivered in June was only down 10% at 25.63 dollars per barrel.