Islamist militants in northern Mali on Monday destroyed the 'sacred' door of one of Timbuktu's three ancient mosques after smashing seven tombs of Muslim saints over the weekend, witnesses said.

"The Islamists have just destroyed the door to the entrance of the Sidi Yahya mosque... they tore the sacred door off which we never open," said a resident of the town.

Islamist rebels in northern Mali smashed four more tombs of ancient Muslim saints in Timbuktu on Sunday as the International Criminal Court warned their campaign of destruction was a war crime.

Malian rebels opened fire on protesters in the northern town of Gao Tuesday, killing at least one person and leaving several injured, witnesses told Agence France Presse.

The march was organized to protest the death of a local government official who was shot on Monday in Gao, which was seized by Tuareg and Islamist rebels nearly three months ago.

Mali's Islamist rebels agreed Monday to start talks on the fate of the desert north they seized this year but mediators Burkina Faso said the group should sever all ties with its Al-Qaeda backers.

Ansar Dine joined forces with a Tuareg rebel group to conquer the entire northern half of Mali in early April, effectively partitioning the landlocked west African country and raising fears of regional destabilization.

An al-Qaida offshoot in Mali which is holding seven Algerian hostages said Sunday negotiations to free them were "advancing" and they had received medication for one of them who is diabetic.

West African military leaders met in Ivory Coast on Saturday to define the mission of a regional security force that could be sent to northern Mali to fight armed groups in control of the north.

The Economic Community of West African States (ECOWAS) says it has a 3,000-man force on standby to enter Mali to help the interim government and try to take back the northern half of the country, now controlled by Tuareg rebels and al-Qaida allies.

The U.N. refugee agency launched an urgent cash appeal on Friday to help thousands uprooted by clashes in Mali, saying that the emergency there had been overlooked.

"This is now an emergency that is six months old and yet we have received only 13 percent of the funds" that are needed, said spokesman Andre Mahecic.

The U.N. Security Council on Wednesday held back support for an African intervention force in Mali, where rebels and al-Qaida allies have taken over the north of the country.

Unrest in Mali, tensions between Sudan and South Sudan, a coup in Guinea-Bissau and Somalia's troubled transitional government dominated annual talks between the U.N. Council and the African Union's Peace and Security Council.

Five people were seriously injured in fighting between Tuareg and Islamist rebels in northern Mali Wednesday, officials said.

Rebel Tuareg fighters of the National Movement for the Liberation of Azawad (MNLA) clashed with Islamist fighters from the Ansar Dine groups overnight in northern Mali, witnesses said Friday.

"Fighters of the MNLA and those of Ansar Dine clashed overnight Thursday to Friday on the outskirts of Kidal," an official from the rebel-held town told Agence France Presse by phone.