ABUJA

Leaders of central and west African states will hold a summit next week to try to draw up a joint strategy against Nigeria's Boko Haram militants, a statement from organisers said Sunday.

The April 8 summit will be the first of its kind since Nigeria's election a week ago which was won by Muhammadu Buhari, a former military leader who has vowed to rid his country of the "terror" of Boko Haram.

"In the face of the mounting and increasingly bloody attacks by the fundamentalists against Nigeria, Niger, Cameroon and Chad and the series consequences for these countries, and the real risk of destabilising western and central Africa, the two organisations have decided to take action," a statement from regional bloc the Economic Community of West African States said.

A coalition involving troops from the four countries has been waging offensives against the Islamists in a bid to crush the insurgency, which has now spread across borders from Boko Haram's stronghold in Nigeria.

The meeting in Malabo, capital of Equatorial Guinea, is being jointly organised by the Economic Community of West African States and the Economic Community of Central African States (ECCAS).

It was not immediately clear if Buhari would be attending as he will not be sworn in as president to succeed incumbent Goodluck Jonathan until May 29.

The Boko Haram insurgency has led to the deaths of more than 15,000 people dead since since 2009, UN rights chief Zeid Ra'ad Al Hussein said last week.

"Countless more children, women and men have been abducted, abused and forcibly recruited, and women and girls have been targeted for particularly horrific abuse, including sexual enslavement.

"This despicable and wanton carnage, which constitutes a clear and urgent menace for development, peace and security, must be stopped," Zeid said.