The fuel price cut in the UK is one of the lowest among European countries that have taken action against the soaring cost of petrol and diesel.
Only Luxembourg has done less than the UK Government out of 13 European nations that have cut petrol taxes since prices began to soar in March, according to the RAC.
The 5p per litre reduction implemented by the UK in March is dwarfed by fuel tax cuts enjoyed by drivers in countries such as Germany (25.1p per litre), Italy (21.2p per litre), Portugal (16.2p per litre), the Netherlands (14.7p per litre) and Ireland (14.5p per litre).
Governments in France and Spain have introduced discounts at forecourt tills worth around 15p per litre and 17p per litre respectively.
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Some fuel retailers, including TotalEnergies in France and BP Spain, have price reductions worth up to about 33p per litre.
Of the 15 European Union states that have not taken steps to lower pump prices since March, all but six already charge less fuel duty than the UK.
UK petrol prices finally started falling in recent days after pressure on retailers to reflect a drop in wholesale costs which began seven weeks ago.
But the UK still has a higher average petrol price of 186p per litre than all European Union members except Finland (190p) and Denmark (also 186p).
RAC fuel spokesman Simon Williams said: “This analysis lays bare an uncomfortable truth for the UK Government – that compared to other European countries, it’s pretty much done the least to support drivers through the current period of record high fuel prices.
“The result is the UK being one of the most expensive places to fill up and putting it above other countries that have historically charged more for fuel than UK retailers do, including France and the Netherlands.
“The cost-of-living crisis shows no signs of coming to an end anytime soon and it’s frustrating that repeated calls to the UK Government for more support are falling on deaf ears.
“UK pump prices might be finally starting to fall, but the reductions so far are too little and too late, given the massive wholesale price drops retailers have been benefiting from for nearly two months.
“Drivers, many of whom depend heavily on their vehicles, need more help and they need it now.”
Commenting, the SNP’s transport spokesperson Gavin Newlands MP said the cost of fuel is now "hammering" households and businesses while the cost of living crisis hits hard.
“Yet the UK Government, and the two Tory candidates vying to be the next UK Prime Minister, are bringing nothing to the table to support people financially through this Tory made cost of living crisis," he said.
“People will be looking across the channel and seeing that many of our EU neighbours are going further and faster to help people with pump costs and energy bills, and wondering why the UK government is not doing the same. This RAC research shows what Scotland could do as an independent country inside the EU."
He went on: “I am pleased the UK government heeded our calls for a fuel VAT cut in March but as always with this UK Government, it was far too little and more still needs to be done.
"Introducing fuel duty regulation would help alleviate some of the cost of living pressure for millions, particularly for businesses and the distribution of goods, as well as those in rural areas.
“I would also urge the UK Government to follow in Scotland’s footsteps by making public transport greener and cheaper, and uprating certain benefits and matching the Scottish Child Payment to get cash into people’s pockets.”
Fuel prices were already rising before Russia’s invasion of Ukraine in February, but the impact of the war has exacerbated the situation.
A reduction in the use of Russian oil has increased demand from other producers, resulting in higher prices.
