The 73-year old will face around a dozen challengers, including Hamadoun Toure, who runs the "Smart Africa" initiative to drive development on the continent via technology, and Modibo Kone, a rural development expert at the West African Development Bank, AFP reports.

The 29 July election has a second round planned for 12 August if no candidate gains an absolute majority of votes.

Elections have been postponed repeatedly since 2013, partly because of security concerns related to Islamist extremism.