OREANDA-NEWS. Simmering tension between Nigeria's oil minister Emmanuel Ibe Kachikwu and state-owned NNPC's managing director Maikanti Baru has broken out into public, adding uncertainty to the pace of badly needed reforms.

In a letter to Nigerian president Muhammadu Buhari, Kachikwu accuses Baru of being engaged in "insubordination" and of "disrespectful and humiliating conducts."

Kachikwu's letter, dated 30 August, was printed widely in Nigerian newspapers. Its provenance has been confirmed by the oil ministry, which described it as "normal procedural correspondence".

The minister's letter follows NNPC's announcement on 29 August of a series of management changes. These had not been approved by the minister or NNPC's board, Kachikwu says in his letter. Kachikwu is chairman of the NNPC board.

"The effect of the attitude of the group managing director [Baru] and the sidelining of the board is that there is a fear culture in NNPC," the letter states.

The high-profile publication of the letter could increase the likelihood of personnel changes at the top of Nigeria's oil industry.