Nigeria’s state oil company on Monday said allegations by the oil minister that the conduct of its group managing director lacked transparency were baseless.

Emmanuel Ibe Kachikwu, in a letter to the president dated Aug. 30 and confirmed by the oil ministry, said Maikanti Baru had bypassed the board on key decisions and did not follow due process.

The Nigerian National Petroleum Corporation, in an emailed statement, said “due process has been followed in the various activities” outlined in the letter.