Sian Powell, Jakarta – Splits have emerged among Aceh separatists on the eve of peace talks with the Indonesian Government in Helsinki, with one faction damning the Finnish negotiators and flatly rejecting special autonomy and another expressing cautious optimism.

Rebel negotiator Nurdin Abdul Rahman yesterday tried to hose down a stinging statement issued by Sofyan Dawood, a Free Aceh Movement (GAM) spokesman in Aceh. "Of course the statement has been confirmed by us," he said. "In the field they have the freedom to express their ideas and how they think or feel."

However, Mr Rahman took a different "tone", he said, adding he preferred to wait for negotiations to continue rather than fight the battle in the public domain.

Special autonomy, he said, had not been ruled out. "We cannot determine whether we will accept special autonomy or anything else, such as self-government. It all depends on the process of the dialogue."

The rebels have been fighting for independence for almost 30 years in a conflict that has left thousands dead. The Helsinki talks which begin today are the first formal negotiations since Jakarta launched a military offensive against the rebels in May 2003.

Sporadic fighting between the Indonesian military and the rebels has continued since the Boxing Day tsunami devastated Aceh, with fire-fights in recent days.

The statement released by Mr Dawood at the weekend roundly condemned a notice on the website of the Finnish negotiators, CMI. "GAM is shocked and dismayed by the recent CMI statement on its website about the supposed aims of the ongoing negotiations," he said in the statement.

"By these statements, CMI betrays the trust the people of Aceh and GAM have given it to act as a neutral mediator. GAM has never agreed that the conflict will or should be resolved within the framework of special autonomy, as CMI states."

In the statement, Mr Dawood asked for the release of Acehnese negotiators held in Javanese jails, and the release of Mohammed Nazar, an activist and Acehnese leader. The CMI website was changed over the weekend, and it is understood the organisation has apologised to the rebels.