More than 20% of Nigerians do not have access to a toilet, a statistic that the president described as "disturbing".

Garba Shehu?@GarShehu

 8.  All enforcement authorities are hereby directed to diligently collaborate with the Federal Ministry of Water Resources in implementing this Order.

Garba Shehu?@GarShehu

The Executive Order 009 came into being against the background that:

 Nigeria is ranked second amongst the nations in the world with the highest number of people practicing open defecation estimated at over 46 million people...

Mr Buhari has set up the Clean Nigeria Campaign Secretariat, which will ensure that "all public places including schools, hotels, fuel stations, places of worship, market places, hospitals and offices [will] have accessible toilets and latrines within their premises".

The president follows in the footsteps of India Prime Minister Narendra Modi, who in 2014 pledged that he would end open defecation.

The number of toilets in India has increased significantly, but a BBC investigation found that many of them are not working or are not being used for various reasons, from lack of running water to poor maintenance to deeply ingrained cultural habits.

In Nigeria, an estimated 87,000 children die from diarrhoea every year, AFP reports citing World Bank data.