France's UN Ambassador Gerard Araud confirmed on Thursday that Mali's interim President Dioncounda Traore had written to French President Francois Hollande and UN Secretary General Ban Ki-moon appealing for military assistance to combat rapidly advancing rebel forces.
Araud said France, Mali's former colonial power, would outline its position on the request on Friday.
Al Qaeda-linked rebels claimed to have driven government forces out of the central city of Konna on Thursday in their push south towards the capital Bamako.
Witnesses reported hours of gun battles, in what is believed to be the fiercest fighting in the nine months since militant groups seized control of a portion of northern Mali larger than France.
"We took the barracks and we control all of the town of Konna," MUJWA rebel group spokesman Oumar Ould Hamaha told news agency Reuters. "The soldiers fled, abandoning their heavy weapons and armored vehicles."
Konna lies about 600 km (375 miles) northeast of the regional capital of Mopti, which is largely seen as a gateway to the country's south. According to UN diplomats, a force of about 1,200 Islamist guerrillas are now 20 kilometers (12.5 miles) from the city.
The UN Security Council met in New York at the request of France on Thursday amid growing international alarm over the latest advance.
In a joint statement the members expressed their "grave concern over the reported military movements." They repeated calls for the restoration of democracy in Mali and urged UN members to "provide assistance to the Malian Defense and Security Forces in order to reduce the threat posed by terrorist organizations and associated groups."
Western and regional states are keen to dislodge the rebels from Mali's north amid fears that it could be used as a launch pad to stage terrorist attacks.
During a brief visit to Bamako on Thursday, UN special representative for the Sahel, Romano Prodi, said the Islamist push was of serious concern and could lead to "extraordinary" decisions from the international community.
"If the offensive continues, I think there will be an emergency decision by the international community," Prodi said.
Last month the Security Council unanimously approved sending an African-led intervention force to help reclaim the territory. No timetable has been given for an intervention, however, and senior UN officials have warned logical constraints will impede a deployment before September.
The three armed Islamist groups at the center of the crisis - al Qaeda in the Islamic Maghreb (AQIM), the Movement for Oneness and Jihad in West Africa (MUJAO), and Ansar Dine (Defenders of the Faith) - all endorse Sharia law. They seized control of the north after hijacking a March 2012 coup led by separatist Tuareg rebels.
Peace talks scheduled to take place between the Malian government, the rebels and separatist Tuaregs in Burkina Faso on Thursday have now been postponed until January 21.
ccp/jr (Reuters, AFP)