MOGADISHU, Somalia – Somalia’s political standoff sharpened on Sunday after former President Sharif Sheikh Ahmed accused the federal government of cutting off basic services, blocking movement and turning security forces against opponents amid an escalating dispute over the country’s elections. Speaking at a news conference in Mogadishu alongside another former leader, Farmajo, Sharif said the authorities had disconnected electricity and water to the compound where he was staying, stopped food from being delivered and barred…