Nigeria's President Muhammadu Buhari appointed former investment banker Kemi Adeosun as finance minister on Wednesday as he swore in 36 members of his long-awaited cabinet.

Buhari has worried investors with the five-month wait to name ministers, at a time when Africa's largest economy is facing its worst crisis in years, hammered by a fall in oil prices and an Islamist insurgency in the northeast.

The 72-year-old former military ruler, who took office on May 29, has said he wanted to take the time to vet the candidates as part of his election promise to battle corruption and mismanagement.

Adeosun is a UK-trained accountant and was most recently the finance commissioner of southwestern Ogun state.

Buhari also appointed Emmanuel Ibe Kachikwu, head of state oil firm NNPC, as junior oil minister, though the president said he would retain overall control of the petroleum ministry.

Okechukwu Enelamah, who headed Nigeria's biggest private equity firm African Capital Alliance, was named minister for industry, trade and investment. Former Lagos state governor Babatunde Fashola became minister for power, works and housing.

Most cabinet members are political veterans, many of whom were key players in Buhari's election campaign.

The new cabinet will have to confront slowing growth, caused by a collapse in oil revenues that has weakened the naira, slashed government revenues and driven up inflation.

The government also needs to win back investors upset by hefty foreign currency restrictions imposed by central bank governor Godwin Emefiele, who filled a vacuum in the absence of a finance minister.