Nigeria, west Africa regional powerhouse, said Tuesday that it would send about 600 troops to Mali as part of a west African military force to wrest control of northern Mali from Islamist extremists.

"Nigeria is expected to send about 600 troops out of the 3,200 (3,300) pledged by ECOWAS," deputy defence minister Olusola Obada said when she received a representative of the British prime minister in the Sahel region in her office.

"I want to say that today, the Sahel is of great concern to everybody in the subregion and the international community. The issue of the Sahel is not an issue localised within West Africa and Africa alone.

The British envoy, Stephen O'Brien, was in Abuja for talks on the rising insecurity in the Sahel, especially the crisis in northern Mali and in areas where Britain can help Nigeria play a crucial role.

"It is of international concern because there we have cells of terrorists that are everyday causing us a lot of problems for the people of Mali," Obada said.

"And I believe that the support that we need to get from the UK and other international partners is to ensure that Mali regains her territory in the North."

Tuareg rebels and armed Islamists, some with links to Al-Qaeda, took control of the vast northern region of Mali, once considered one of west Africa's most stable democracies, after a March coup in the capital Bamako created a power vacuum.

Regional west African bloc ECOWAS agreed earlier this month to send 3,300 troops to Mali.

European Union foreign ministers have agreed in principle to send a military mission to train Mali combat units.

The African Union has also endorsed a plan for military intervention to regain control of Mali's desert north and restore the authority of the state.

The force will be composed of troops from Nigeria, Senegal, Niger, Burkina Faso, Ghana and Togo but also possibly from countries outside the region.