At last, Nigeria and its neighbours - Chad, Niger, Cameroon and Benin - seem to have a plan for their Multi-National Joint Task Force (MNJTF) to fight Boko Haram's Islamist militants. This plan should be approved by the African Union through a vote on Tuesday.

But what are the chances that this 8,700-strong regional force will root out an insurgency responsible for the death of tens of thousands in recent years?

The area that the MNJTF will be covering draws the force's first limit.

Military and diplomatic sources have confirmed that MNJTF soldiers will only operate between the outskirts of Niger's Diffa border town, and the towns of Baga and Gambaru in Nigeria.

In other words, the regional force's main task will be to secure the Nigerian side of Lake Chad, which represents "only 10 to 15% of the entire area where Boko Haram operates", according to a diplomat based in the region, who spoke on the condition of anonymity.

"This plan won't solve the problem, it will remain up to Nigeria to do most of the job," the source added.

As a matter of fact, Nigeria remains extremely reluctant to have an international force on its territory.

Africa's giant would rather show that it can lead regional operations or at least be part of them - Chad in the 1980s, Sierra Leone and Liberia in the 1990s; Darfur later - than host foreign armies to solve trouble at home.

Nigeria has always remained very protective of its territorial sovereignty since the Biafra war.