Less than half of the fuel duty cut announced by Rishi Sunak has been passed on to drivers filling up at pumps, according to the AA. The 5p-a-litre reduction in fuel duty came into force at 6pm on Wednesday after the chancellor announced the measure in his spring statement amid the soaring cost of living. Petrol and diesel prices had hit highs of 167.3p and 179.72p a litre respectively, before Sunak’s announcement. The AA said that on Thursday the average price of petrol across the UK was 164.59p a litre, with diesel at 178.13p. “Although we have to accept that, for many forecourts, the duty cut comes through with the next delivery of fuel, the size of the fall is very disappointing,” said Luke Bosdet, the fuel price spokesman at the AA. “I expect the government will be watching very closely to see if pump prices reflect more of the fuel duty cut over the weekend.” However, Bosdet said drivers had noted that some Asda forecourts moved to drop prices even before the chancellor’s 6pm cut in fuel duty came into effect. The AA said that while the wholesale cost of diesel has been climbing, petrol has dropped “substantially” since hitting a peak at the end of the first week of March. “That should have brought a further 6p-a-litre cut in pump prices, effectively doubling the saving from the fuel duty cut,” he said. “For now, the message to drivers is clear, head to the cheaper forecourts, you can’t miss them.” While the chancellor’s spring statement offered some tax cuts, including a £3,000 increase in the threshold for national insurance contributions, it has received widespread criticism for failing to support poorer families and other vulnerable groups from soaring inflation. The New Economics Foundation said only 7% of the savings from cutting fuel duty would go to the poorest fifth of households, given that more than half do not have a car. By contrast, a third of the savings from the fuel duty cut will go to the richest fifth of households.