Mr Buhari is leading discussions in the capital Abuja on how to save the Lake Chad from extinction.

Lake Chad is literally drying up in front of peoples' eyes: it has shrunk by 90% in the past four decades, thanks, in part, to a combination of climate change and mismanagement.

The lake is the main source of freshwater for 40 million people, mainly in Nigeria, Niger, Chad and Cameroon.But as it dries up and hunger rises, the region has become fragile - migration and resettlement has intensified as farmers and fishermen have been confronted with leaner harvest, while pastoralists move out in search of water and food for their cattle.

Boko Haram jihadists have also targeted subsistence farmers and fishermen to fill their ranks.

Mr Buhari has been joined at the Unesco-backed conference by other regional leaders and representatives from more than 30 countries.At the end of the conference today, the regional leaders will decide if the options available to them to save the lake and make the basin habitable again, are practical and realistic and determine if there is political will to go ahead.