British farmers are facing one of their toughest financial squeezes in years as the Iran conflict drives agricultural costs sharply higher.Fertiliser prices have jumped 30 per cent and fuel costs have doubled, pushing “agflation” to 7.6 per cent in March — more than double the wider economy’s three per cent rate. It is the fastest rise in farming input costs since Russia’s invasion of Ukraine in early 2022.Unlike that period, when higher commodi…