Nigeria's outgoing President Goodluck Jonathan is alleged to have secretly awarded the frequency spectrum recently offered for public auction by the Nigerian Communications Commission (NCC).

Media reports revealed the licences for the spectrum, valued at about $1 billion were awarded to Globacom and Visafone.

Several Nigerian news portals have stated that the licensing did not pass through the normal bidding process, thereby preventing the NCC from advertising and supervising an auction.

It has been reported that President Jonathan directed that the 800MHz spectrum be issued to Jim Ovia, founder of Visafone, while the 700MHz spectrum was awarded to Mike Adenuga, who owns Globacom.

The spectrum became available following the migration of broadcasting from analogue to digital, thereby freeing part of the electromagnetic spectrum previously used for broadcasting. Digital TV typically requires fewer spectrums than analogue.

Ovia co-headed Nigerian government's 14-man committee set up by President Jonathan in 2012 to develop the policy on a five-year broadband penetration in Nigeria.

He was also a member of the 19-man Broadbank Council charged with implementing the policy proposed by the presidential committee.

Ovia, the former managing director of Zenith Bank, is seen as a close associate of Jonathan; he was linked to the emergence of Godwin Emefiele, his successor at Zenith Bank, as the governor of the Central Bank of Nigeria.

The incoming administration, headed by Muhammadu Buhari, is planning to probe the protocol through which the spectrums were awarded.

Buhari's administration is also planning to investigate other controversial spectrum sales conducted by NCC, including the secret sale of a spectrum belonging to the Nigerian Police to Open Skys, as well as the spectrum that was sold to South African investors behind Smile Communications.