President Muhammadu Buhari on Tuesday blamed clashes between Muslim cattle herders and Christian farmers on the clamour for land in the face of a population rapidly approaching 200 million people.

At least 83 people have been killed in the communal violence since Dec. 31.

Muhammadu Buhari, who called for calm, has already ordered a heightened police presence in the central state of Benue, where most of the killings took place in the last few weeks, including the relocation of the country's police chief.

Muslim herdsmen, mainly of the Fulani ethnic group, and Christian farmers often clash over the use of land in parts of central Nigeria, known as the Middle Belt.

"Mr Buhari holds the view, as do many experts, that these conflicts are more often than not, as a result of major demographic changes in Nigeria," said an emailed statement issued by the presidency.

"While the land size has not changed and will not change, urban sprawl and development have simply reduced land area both for peasant farming and cattle grazing," said the statement, urging people to remain calm and cooperate with security agencies.

It said Nigeria's population was around 63 million when the west African country gained independence in 1960, compared with a population now "estimated at close to 200 million".

United Nations estimates that Africa's most populous country is set to become the country with the world's third largest population, behind India and China, by 2050.

The presidency said a conference would be set up in an attempt to identify short and long term solutions to the problem of clashes between the semi-nomadic farmers and the mostly settled farmers.

The Middle Belt region is a diverse region in which differing religious, ancestral and cultural differences have frequently kindled conflict in the last few decades.

Despite the most recent outbreaks of violence, Nigerians, split roughly equally between Christians and Muslims from around 250 different ethnic groups, mostly live peacefully together.

Reuters