The average price of UK petrol rose by 5.44p a litre in April, the second biggest monthly increase since 2000. Data from the RAC revealed a litre of unleaded shot up from 122.62p to 128.06p on average, with the retailer increases driven by a 5% jump in the cost of a barrel of oil.

Diesel increased by a more modest 3p a litre at the pumps, to 133.7p, though the RAC notes that the difference between the fuels in the wholesale price that retailers pay was only a penny. Britain’s four supermarket fuel retailers - Tesco, Sainsbury’s, Morrisons and Asda - increased their petrol prices above the UK average, too. 

The price rise was most evident in Wales, where the cost of unleaded rose from 121.37p to 127.47p per litre over the course of the month, while London ended April with the most expensive petrol at just over 129p per litre. 

The RAC cites the example of filling an average family car’s 55-litre fuel tank with petrol, which went up by £3, to £70.43, across the UK in April.  

RAC fuel spokesman Simon Williams claims “it is very clear from our monitoring of forecourt and wholesales prices that retailers have been using the cheaper wholesale cost of diesel to subsidise petrol pump prices and had they not, a new monthly price rise record would have been set.

“To put this pricing discrepancy in perspective, last year the amount of diesel sold was almost double that of petrol.” 

The news comes as the Committee for Climate Change calls for the UK government to bring forward its 2040 ban on new diesel and petrol vehicles to 2030, reigniting the debate around the UK road infrastructure's readiness for mass electrification. 

A detailed breakdown of UK fuel pricing changes since the beginning of 2015 can be found on the RAC's Fuel Watch website.