The call comes after Islamist militants said they had entered the key central town of Konna.

The UN has approved plans to send some 3,000 African troops to Mali to recapture the desert north, which is controlled by the militants.

On Friday, French President Francois Hollande said France would only help Mali within a UN framework.

He was speaking after UN diplomats revealed that Malian President Dioncounda Traore had asked France - the country's former colonial power - to help counter the rebel offensive.