Drivers face paying an extra £16 for a full tank of petrol compared to last December, figures show.
It comes as the industry has urged supermarkets and retailers to lower prices in line with falling wholesale costs – instead of raising them.
For every litre, motorists are paying 30p more at the pumps than 12 months ago as millions hit the road to see friends and family over the festive break.
That’s despite wholesale petrol and diesel coming in at just 18p per litre.
It means the 18million drivers on the road this Christmas will be overpaying by around £2million.
But ministers are ignoring calls for an independent watchdog to regulate them.
The RAC, AA and campaign group FairFuelUK have repeatedly demanded supermarkets make cuts.
Boris Johnson is under pressure to follow US President Joe Biden in an official investigation to stop the rip-off.
Tory MP Craig Mackinlay, chairman of the All-Party Parliamentary Group for Fair Fuel, said: “Efforts to work with the fuel industry so that pump prices are market driven, are not working.
“Nearly £2billion of falls in wholesale prices have not been passed on.
"This is bad for the economy, bad for inflation, bad for business and bad for jobs.”
Another Tory Rob Halfon insisted: “Struggling families need a PumpWatch regulator.”
Howard Cox, of FairFuelUK, said Brits are paying “scandalous prices generated by greedy wholesalers and fuel brokers”.
Are petrol prices out of control? Let us know in the comments section below
Tips to save on fuel
1. Fill up at busy petrol stations
These stations buy more fuel and can take advantage of falling prices. “The big petrol stations have deliveries every day so they can change the price,” Arthur Renshaw, of petrol station analyst Catalist Experian, told The Mirror . “But a small petrol station in a village may have a delivery every couple of weeks.”
2. Choose a big station
Stations buy their fuel on the wholesale market. Just as in any other negotiation, the big buyers are better able to strike a deal.
3. Look for a cluster of stations
When several stations are close together, they are more likely to cut prices to tempt drivers in. “If you are in the Highlands and Islands of Scotland, you have much less competition than in the centre of Manchester,” said Renshaw.
4. Do your research
The website PetrolPrices.com allows you to compare prices in your area. It also lists the latest average prices, so you know if you’re being ripped off.
5. Play the supermarket game
Supermarkets are competing on fuel prices along with everything else. When you’re shopping, keep an eye out for vouchers offering petrol discounts. But be aware of the overall cost.
“That is one way to get prices down below £1, but you do need to buy a lot of food to get that result,” PetrolPrices.com owner Peter Zaborszky said.
6. Stop by provincial towns
Airports, motorways, expensive cities and rural areas have the highest charges, according to PetrolPrices.com analysis. “The golden path is down the middle where rent is cheap,” Zaborszky explained.
