Islamists occupying Timbuktu in northern Mali were using pickaxes on Sunday to destroy any remaining mausoleums in the ancient city, an Islamist leader said.

"Not a single mausoleum will remain in Timbuktu, Allah doesn't like it. We are in the process of smashing all the hidden mausoleums in the area," an Ansar Dine leader, Abou Dardar, told Agence France Presse.

Ansar Dine and MNLA, armed rebel groups active in northern Mali, on Friday announced their commitment to ceasing hostilities and denounced U.N. Security Council approval of a military intervention force.

The Security Council resolution adopted on Thursday gave an African-led military force an initial one-year mandate to use "all necessary measures" to help Mali's government reconquer the north from Islamist militants.

Gunmen who abducted a Frenchman in northern Nigeria probably have links to al Qaida's north African group or to Islamist groups in northern Mali, French President Francois Hollande said Friday.

"He was captured by a heavily armed group which killed two Nigerians and is probably linked to AQIM (Al-Qaida in the Islamic Maghreb) or the groups which are today in Mali," he told a French radio station.

The U.N. Security Council on Thursday unanimously approved sending an African-led intervention force to help Mali's army reconquer much of the country from Islamist militants.

The 15-member council gave the force an initial one year mandate to use "all necessary measures" to help the Mali government take back the northern half of the country from "terrorist, extremist and armed groups."

Crisis talks with the Islamist militants occupying northern Mali need to go hand in hand with credible preparations for an African-led military intervention, the United Nations' special envoy for West Africa said Wednesday.

"No pacifist solution will be possible without credible military preparation," U.N. envoy for the Sahel region Romano Prodi said after talks with Niger's President Mahamadou Issoufou.

With his head bowed, Moctar Toure recalls the day two months ago when hardline Islamists blindfolded him and chopped off his right hand, robbing him of his independence and his livelihood.

"It is not our arms they cut off, but our lives which they stole," says the 25-year old.

The U.N. Security Council on Tuesday condemned the arrest of Mali's prime minister by the armed forces and renewed a threat to impose sanctions on those who threaten the country's "constitutional order."

U.N. leader Ban Ki-moon is also "troubled" by the new turmoil in the African nation, where Islamist militants and rebels have taken over half the country, his spokesman said.

Malian Prime Minister Cheick Modibo Diarra resigned on Tuesday, hours after influential former coup leader Captain Amadou Sanogo ordered soldiers to arrest him at his home.

The ex-junta claims the move was not a coup, however Diarra's resignation plunges further into crisis a troubled nation which had over half its territory seized by Islamic extremists after Sanogo ousted its government in March.

A growing number of Malians, including in the military, feel abandoned by the international community and are advocating unilateral action to reclaim the north from Islamist militia if foreign armies are too slow to the rescue.

The transitional government in Bamako which still has control over Mali's southern half made a fresh appeal to the United Nations Security Council on December 5 for a 3,300-strong regional standby force to intervene.

The Malian government and two rebel groups agreed Tuesday to respect Mali's "national unity" as they held their first talks to try to end the crisis that has split the west African country in two.

Delegations from the government, the Islamist Ansar Dine and the Tuareg MNLA agreed "on the respect for Mali's national unity and territorial integrity," and "on the rejection of any form of extremism and terrorism," they said in a statement.