One of the main Islamist groups in Mali split Thursday, with the breakaway faction saying it was ready for talks to end a two-week-old French-led offensive, amid mounting concerns over rights abuses by government troops.
The first of the 6,000 troops pledged by African nations to support France's intervention started heading north, moving closer to the areas a triad of Al Qaeda-linked groups seized in April.
Cracks emerged in the rebel front however when a new faction announced it had broken away from Ansar Dine (Defenders of the Faith).
The newly-formed Islamic Movement for Azawad said in a statement that it "rejected all forms of extremism and terrorism and was committed to fighting them", adding that it wanted a "peaceful solution" to the Mali crisis.
The use of the Tamasheq term Azawad appeared to further signal a willingness among the group's Tuareg ranks to distance themselves from Al-Qaeda in Islamic Maghreb (AQIM) and the Malian insurgency's mainly foreign leadership.
The statement said the new group was composed entirely of Malian nationals and called on "Malian authorities and France to cease hostilities in the zones that we are occupying in the north-eastern regions of Kidal and Menaka to create a climate of peace which will pave the way for an inclusive political dialogue."
The new group is led by Alghabasse Ag Intalla, the scion of a leading Tuareg family from Kidal, and a former negotiator from the group's moderate wing.
West African and Algerian negotiators have for months been trying to get Ansar Dine to sever links with AQIM and its offshoot the Movement for Oneness and Jihad in West Africa (MUJAO), essentially comprising foreign fighters.
The UN has authorised the deployment of a 3,300-strong force under the auspices of 15-nation West African bloc ECOWAS. The involvement of non-member Chad could boost the African deployment by another 2,000 soldiers.
Most of the estimated 1,000 African soldiers who have arrived in Mali are still in Bamako but a Malian defence source said a group of 160 troops from Burkina Faso had started making its way to central regions nearer the frontline.
Paris' surprise decision to intervene on January 11 received broad international support but reports of abuses by the Malian troops advancing in the wake of the French advance have caused concern.
The European Union said it was worried at reports that Tuaregs and Arabs had been killed by Malian forces, stoking fears of systematic reprisals against the region's light-skinned residents.
"We are very worried by reports evoking the possibility of ethnic attacks and fighting and abuses committed in revenge attacks," said EU humanitarian aid commissioner Kristalina Georgieva in remarks translated in French.
The International Federation of Human Rights Leagues said that in the central town of Sevare at least 11 people were executed in a military camp near the bus station and the town's hospital, citing evidence gathered by local researchers.
Twenty others were executed in the same area and the bodies dumped in wells or otherwise disposed of, the organisation said, adding that two Tuaregs were executed by Malian soldiers in the central town of Niono.
The organisation called for an immediate independent inquiry to "determine the scale of the abuses and to punish the perpetrators".
Human Rights Watch said its investigators had spoken to witnesses who saw the executions of two Tuareg men in the village of Siribala, near Niono.
The group also said witnesses had reported "credible information" of soldiers sexually abusing women in a village near Sevare, and called on the government to urgently investigate these incidents.
French Defence Minister Jean-Yves Le Drian urged extreme "vigilance" against any abuses, saying the "honour of the (Malian) troops is at stake".
France said it had already deployed 2,300 soldiers in Mali, a former colony, whose poorly trained and equipped force has been overwhelmed by Islamist rebels occupying the vast arid north and seeking to push south.
International moves to support the French-led operation gathered pace, with the US military airlifting French troops and equipment from France into Mali.
Mali's year-old crisis began when Tuaregs returning from fighting for slain dictator Moamer Kadhafi in Libya, battle-hardened and with a massive arsenal, took up a decades-old rebellion for independence of the north, which they call Azawad.
They allied with hardline Islamists and seized the key towns of Kidal, Gao and Timbuktu in a matter of days.
The Islamists later broke with their Tuareg allies, and with firm control of the north, implemented an extreme form of Islamic law.