Nigerian President Goodluck Jonathan is facing the biggest test of his three years in office after reports the central bank questioned the lack of accounting for $50 billion in oil revenue and a former leader criticized him for failing to tackle corruption. Former President Olusegun Obasanjo, a stalwart of the ruling People’s Democratic Party , said in a letter to Jonathan this month that he has failed to tackle graft and security threats in Africa ’s biggest oil producer. He also accused him of widening a split between the mainly Muslim north and largely Christian south in a bid to retain power. Obasanjo’s criticism came after newspapers including Lagos-based ThisDay said Central Bank of Nigeria Governor Lamido Sanusi wrote Jonathan a letter alleging that the Nigerian National Petroleum Corp. is withholding more than three-quarters of oil revenue earned from January 2012 to July this year. The […]