The RAC has issued a stark warning to motorists about rising fuel prices as the ongoing Iran war threatens to further push up costs. Prices fell at the back end of April but are now nearing the highest since the war began in late February. There is likely to be worse to come if the wholesale costs of fuel stay as they are. The RAC said pump prices hit 158p for petrol and 191p for diesel on April 15. They drifted back from that on the hope that Donald Trump might at least cut a deal with Iran to reopen the crucial Strait of Hormuz waterway between the Persian Gulf and the Gulf of Oman, through which a large proportion of the world’s oil is transported. Motoring groups at the time complained that prices for drivers did not fall as quickly as they should, given that the oil price had fallen well below its highest level. On Tuesday, oil prices were down 2.3 per cent to $103.95 a barrel, but experts warn the worst could be yet to come.…