A 10p cut in fuel duty should be introduced to help motorists deal with the rising cost of petrol and diesel caused by the Iran war, Sir Ed Davey has said. The Liberal Democrat leader also called for a 10% cut in rail fares to help travellers with cost-of-living pressures. Sir Ed’s offer to deal with living costs comes after other opposition parties have set out their plans to lower the price of petrol and home energy bills.