The federal Government has sent an air force technical team and the commander of a planned African-led force to Mali to assist the country's military as it battles Islamists, a presidency spokesman said Saturday.

The confirmation of Nigerian military personnel on the ground comes after French air power helped Mali mount an offensive against the Islamists who control the country's north and who have been seeking to push further south.

However, it was not yet clear when a planned 3,000-strong African-led force could be sent despite 15-nation west African bloc ECOWAS giving its go-ahead on Friday for the immediate deployment of troops.

The Islamists' advance in Mali has raised fears that the country could provide a safe haven for Al Qaeda-linked extremists, posing a threat to the region as well as Europe and beyond.

Nigeria has the largest military in the 15-nation Economic Community of West African States, but it is also battling an insurgency by Islamist extremist group Boko Haram at home in its northern and central regions.

"The technical staff from the Nigerian air force are already on the ground in Mali," Nigerian presidency spokesman Reuben Abati told AFP. "They are not fighters; they are technical staff."