ABUJA: Nigeria has boosted its troop allotment for Mali to 1,200 soldiers from 900 planned earlier as part of an African force aimed at helping the country retake its Islamist-controlled north, officials said Friday.

In a letter to the country's Senate on Thursday, President Goodluck Jonathan said he had, "in consultation with the National Defence Council, approved the development of a contingent of 1,200 members of the Armed Forces."

It said the soldiers would be deployed "for limited combat duties". Nigeria will also command the African force.

In urging the Senate to approve the deployment, Jonathan said he had concluded that "our national security is under imminent threat or danger as a result of the crisis in northern Mali."

The Senate approved the deployment on Thursday, Senator Ita Enang, chairman of the body's business and rules committee, confirmed on Friday.

A contingent of 80 Nigerian troops departed for Mali on Thursday as part of the UN-mandated African force, and military officials spoke then of a total of only 900 troops. It was not clear when the remainder of the troops would arrive.

Lieutenant General Azubuike Ihejerika, speaking shortly before the troops left for Mali, made reference to reports that members of Nigerian Islamist extremist group Boko Haram had trained in Mali.

France said it already has 1,400 soldiers in Mali and that its contingent would gradually be increased to 2,500 troops.