Ibrahim Assaley, a member of the Tuareg rebel National Movement for the Liberation of Azawad (MNLA),  said they had refused to agree to a final statement on an Islamic state, because it differed from a protocol agreement they had signed earlier.

Ansa Dine official Moussa Ag Asherif confirmed that there had been an impasse in talks just 48 hours after the two groups had announced plans for joint domination of the remote desert region.

Ansar Dine is backed by al-Qaeda's north African branch, known as al-Qaeda in the Islamic Maghreb (AQIM).

The MNLA's Ibrahim Assaley told the news agency AFP that Ansar Dine spoke of applying "pure and hard" Islamic Sharia law and banning non-Muslim groups from the area. "It was as if they wanted to dissolve us into Ansar Dine. That is unacceptable," Assaley said.

Ansar Dine's Asherif said the original accord had been merely a starting point for working discussions and the deal was on a take it or leave it basis.

Local media reported that Ansar Dine had signed a deal in Gao to merge with the separatist rebels on Saturday. The original declaration spoke of a separate Islamist state in Mali's vast desert north which covers an area larger than France.          

Civilians in Gao were reported to be struggling to adjust to new rules in force under sharia law.

A television report said "couples were not allowed to show affection in public, women must cover their heads at all times and all bars and live music venues have been closed."

Islamic state rejected by transitional government and ECOWAS

Martin Vogl is a journalist in the Malian capital Bamako. He says both groups had to make pretty serious concessions to come to their initial agreement. "The Islamic group had been saying beforehand that they were against independence for north Mali, but are now saying they are backing it. The Tuareg rebels had said they were against an Islamic state; they had wanted a secular state," he told DW.      

Mali's embattled transitional government had swiftly rejected the declaration by the embryonic rebel alliance.

"The government of Mali categorically rejects the idea of the creation of an Azawad state, even more so of an Islamic state," said Hamadoun Toure, information minister in the transitional administration.

The West African bloc ECOWAS has also rejected the rebel declaration of independence and repeated an earlier threat to take "all necessary measures" to keep Mali intact.

However, ECOWAS mediator and Burkina Faso foreign minister, Djibrill Bassole, injected a note of ambivalence, saying it was always better to negotiate with a single group rather than with several groups whose interests are sometimes diametrically opposed.  

ECOWAS has been preparing a 3,000 strong force for potential deployment to Mali. The bloc is said to be waiting for a formal request from Malian authorities before sending in troops.  

Author: Mark Caldwell (afp, dpa)

Editor: Susan Houlton