Coordinating Minister for the economy and Minister of Finance, Dr. Ngozi Okonjo-Iweala The Federal Government on Wednesday expressed concern about the scarcity of petrol being witnessed in most parts of the country, stating that oil marketers would today (Thursday) receive the sum of N156bn as arrears of their subsidy claims. The Minister of Finance, Dr. Ngozi Okonjo-Iweala, stated this in Abuja in an interview with journalists shortly after declaring open the 20th conference of Directors General of Customs of the World Customs Organisation.