The acting head of the African Union and the president of Chad issued a joint call on Tuesday for the United Nations to rapidly authorize an intervention force for Islamist-held northern Mali.

The call came after a meeting between Benin's President Thomas Boni Yayi, acting head of the African Union, his Chad counterpart Idriss Deby as well as Mali's Prime Minister Cheick Modibo Diarra, the Chadian foreign ministry said.

Burkina Faso President Blaise Compaore, west Africa's chief mediator for the crisis in Mali, will hold his first joint meeting Tuesday with delegations from the Malian government and armed groups Ansar Dine and the MNLA, his office said.

"The president will receive all the delegations together tomorrow at 4:00 pm (1600 GMT)," the presidency said Monday, after Compaore met representatives from Mali's transitional government.

U.N. leader Ban Ki-moon said Wednesday the Security Council should approve a military attack on Islamic militants in Mali only if African nations can answer "fundamental questions" on their proposed force.

The U.N. leader said in a report that any operation in northern Mali carries major humanitarian and human rights risks even though it is becoming necessary because of mounting abuses by the "terrorist and affiliated" militants.

Mali's Prime Minister Cheick Modibo Diarra arrived in Paris on Monday for talks with senior officials on plans for a military intervention to dislodge Islamists in control of the vast north.

Diarra's office said he would meet Foreign Minister Laurent Fabius on Tuesday to discuss "French support for reclaiming regions illegally occupied by terrorists".

A Mauritanian news website on Monday published images of a French citizen kidnapped last week by one of the armed Islamist groups controlling the north of neighboring Mali.

Two photos published on the site Alakhbar showed the man, identified as Alberto Rodriguez Leal, 61, with his head bowed, wearing a blue shirt and flanked by two armed men dressed in kakhi robes.

Mali's interim regime on Sunday postponed three days of national talks aimed at planning a transition back to democracy and tackling the security crisis in the Islamist-occupied north.

"The days of national consultations have been postponed to December 10, 11 and 12," an official statement said. The national meeting was due to start on Monday in Bamako.

The Movement for Oneness and Jihad in West Africa (MUJAO), one of the Islamist groups occupying northern Mali, on Thursday claimed responsibility for the kidnapping of a French citizen two days ago.

"We claim responsibility for the kidnapping of the Frenchman in south-western Mali near the Mauritanian border," said MUJAO spokesman Abu Walid Sahraoui. They would post a video of the hostage shortly, he added.

Dozens of people have been killed in clashes between Islamic radicals and secular Tuareg fighters in northern Mali since Friday, witnesses and officials said.

"It's a real massacre, there are dozens dead," said a Malian security source, referring to the fighting in the region of Gao. Witnesses on the ground confirmed the scale of the clashes.

EU foreign ministers agreed in principle Monday to send a military training mission to Mali to support regional African efforts to wrest control of the north of the country from armed Islamists.

Under the plan, some 250 European officers would be sent to train Malian combat units and help restructure the country's weakened army in a mission that could start as early as January and last through the year.

The Algerian army has killed three Islamists in the restive Kabylie region, including Al-Qaida in the Islamic Maghreb's top military commander, several Algerian newspapers reported on Monday.

Rabah Makhfi, 45, also known as Sheikh Nacer and considered AQMI leader Abdelmalek Droukdel's right hand man, was among the three killed in Bejaia, 250 kilometers (155 miles) east of Algiers, on Friday, Arabic-language daily Ennahar reported.