Ansar Dine is one of the main armed groups controlling northern Mali's vast desert since a rebellion in April that Western and regional powers fear could provide a haven for Islamist radicals to plot international attacks.

"Ansar Dine has no choice but to suspend its offer to cease hostilities, which was hard-won by the mediators but mocked by the Malians," the group said in a statement dated Dec. 26 and seen by Reuters on Friday.

Mali's government, Ansar Dine, and Tuareg separatist group MNLA agreed to end hostilities at peace talks organised by regional mediator Burkina Faso on Dec. 5.

Islamist group MUJWA, seen as having strong ties with al Qaeda's Saharan wing, was excluded from the talks and has continued to fight on.

The diplomatic effort to conclude peace with Ansar Dine and the MNLA however coincided with preparations for a deployment of thousands of Western-backed African troops to reclaim northern Mali from the rebels.

The United Nations Security Council on Dec. 20 authorised the intervention and also authorised the European Union and other UN member states to help build up Malian security forces for the war.

No military offensive is expected before late this year.

"Ansar Dine has not seen any sincere desire on the part of the Malian government for peace," the group said. "On the contrary, while our delegations were in (Burkina Faso's capital) Ouagadougou to open talks, the Malian government was living by war and invective," it said.

Islamist rebels have destroyed much of northern Mali's religious heritage and carried out a string of amputations in the name of imposing its strict interpretation Islamic law on a population that has practised a moderate form of Islam for centuries.

Some 400,000 people have fled their homes in Mali this year. The rebellion was launched by separatist Tuareg rebels but has since been hijacked by better armed and funded Islamists and al Qaeda fighters in the Sahara.

Center>Copyright Reuters, 2013