Nigeria’s Oil Minister, Emmanuel Ibe Kachikwu, has been ousted from his position and appointed as the Group Managing Director of state oil company NNPC, Reuters reported. NNPC Group Executive Director for Exploration and Production, Maikanti Kacalla Baru, will take the reins from Kachikwu, while he remains as the company’s board chairman.

Nigerian President, Muhammadu Buhari, had appointed Kachikwu as a junior minister last year, while he kept the petroleum minister portfolio for himself in order to oversee energy sector reforms. According to Trade Arabia, the reshuffle came as part of a wider NNPC board overhaul by the president.

President Buhari has accused the previous administration of failing to save finances when crude oil cost more than $100 a barrel. In 2013 the central bank governor said that tens of billions of dollars in oil revenue had failed to make it into state coffers, which the NNPC denied. Antony Goldman, head of Nigeria-focused PM Consulting, said: “Reconstituting the board appears to be an attempt to adopt a different approach with a sense of proper oversight and accountability.”

Oil accounts for about 70% of Nigeria’ revenue, but the OPEC member has been hit hard by a prolonged drop in crude prices that has caused the deepest crisis in Africa’s biggest economy for more than a decade.