Fuel forecourts have been accused of profiteering after petrol and diesel prices increased sharply over the last few days, despite selling stocks bought before the current Middle East conflict.

The AA has already warned that fuel costs could return to where they were at the start of the year after Iran threatened to attack vessels passing through the Strait of Hormuz in the south of the country.

But despite industry experts saying any increase in the price of Brent crude would take time to filter through to forecourts, the FairFuelUK campaign said it had been contacted by more than 120 supporters complaining that prices were now rising.

Howard Cox, FairFuelUK founder, said: “Most of these forecourts, many believe, are selling fuel at these higher prices even though they bought these stocks before any wholesale rises.

“It seems opportunistic profiteering is rife once again.”

The Petrol Retailers Association (PRA) said the US and Israel’s war on Iran had increased the cost of petrol and diesel and pump prices would have to go up: “Rising fuel prices hurt the economy in the form of higher inflation, impacting already hard-pressed household budgets,” said PRA director Gordon Balmer.

“To help motorists and businesses, I am today writing to the Chancellor urging her to abandon the planned fuel duty increases.”

The RAC said the UK shouldn’t see a shock jump in prices because wholesale fuel costs had only been rising gradually recently

“Knowing the tendency for price increases to be passed on far more quickly than cuts, on behalf of drivers we urge retailers not to put up the price of fuel they’ve already got in forecourt tanks and reflect any increases in wholesale fuel fairly on the forecourt,” added RAC head of policy Simon Williams.