A litre of unleaded now costs 135.13p, up from 131.76p at the start of the month.

Diesel now costs on average 137.06p per litre, up from 134.36p.

The price rises meant that last month was the most expensive July to fill up with petrol since 2013, and for diesel since 2014.

A driver filling up a 55-litre car with petrol now pays on average £3.08 more to fill up than they did at the start of June, and £11.47 more than they did a year ago.

For diesel drivers, filling a similarly sized tank now costs £2.90 more than at the start of June, and £10.46 more than it did at the end of July 2020.

Simon Williams, RAC fuel spokesperson, said: “While we’re not past the pandemic by any means, demand for oil is likely to continue to increase as economic activity picks up again, and this is likely to have the effect of pushing up wholesale fuel prices, costs which retailers are bound to pass on at the pumps.

“Unless major oil producing nations decide a new strategy to increase output, we could very well see forecourt prices going even higher towards the end of the summer.”

The eight-year high comes as families set off on summer staycations.

The RAC recommends they fill up at supermarkets where a litre of petrol is around 3p cheaper compared to the average (132.34p compared to 135.13p) and more than 16p less than at motorway service areas (132.34p compared to 148.78p).