Three prominent opposition members resigned from the Syrian National Council on Tuesday, saying they have given up on trying to make the group a more effective.
“We are resigning because our effort to make the group a more effective player in the revolt against President Bashar al-Assad's rule has not been too successful.
Haitham al-Maleh, a former judge and long-standing dissident against four decades of Assad family rule, was joined by opposition leader Kamal al-Labwani and human rights lawyer Catherine al-Talli in announcing their resignation.
Their departure comes at a time when the West and Arab powers are raising the pressure on the opposition to unite and show it can lead the uprising against Assad.
A SNC member who requested anonymity said 80 members of the 270-strong group also planned to defect and may form a new opposition movement to focus on arming the rebels fighting government forces in Syria.
Thousands of people have died in the year-long revolt against Assad and a strong leadership has yet to emerge from the opposition.
The SNC has been an international voice for the opposition but activists inside Syria complain the mostly exiled leadership has little connection to protesters on the ground.
Some activists have raised questions about the fate of money pledged by some Arab and Western powers to the SNC.
“People are angry about the executive board. We don't know what it is doing and it's not clear how they are spending the money being given to them or how much they have received,''said Salam Shawaf, an independent Syrian activist based in Cairo.
Maleh told Reuters he was frustrated by a lack of transparency and organisation in the SNC, a group led mostly by opposition figures who had fled abroad and have been negotiating with foreign powers to support the revolt.
“I have resigned from the SNC because there is a lot of chaos in the group and not a lot of clarity over what they can accomplish right now. We have not gotten very far in working to arm the rebels,''Maleh, an Islamist leaning liberal, said.
Maleh, who was a member of the SNC's executive board, echoed some activists' complaints that the group has been too slow to push for arming the rebels.
His resignation may be part of a struggle over leadership roles in the opposition, with some dissidents regarding the Muslim Brotherhood as having too much influence over the SNC.
Labwani, a liberal who formed a group within the SNC called the Syrian Patriotic Group, said the SNC “is incapable of representing the aspirations of the Syrian people at a time the repressive regime is committing more criminality''.
“We have exhausted all means to reform. All the ways to change the SNC have been blocked in our face. We are calling for a group resignation from the Syrian Patriotic Group,''he said, declining to give a number of potential defections.
Talli, who was also on the SNC executive board, said she decided to resign so as not to be held responsible for the shortcomings of the SNC and its political mistakes.
Labwani, a physician released after six years in jail last December, implied a power struggle was underway within the SNC, although he declined to give details.
“We hope to arrange a conference to find a way to create a true and democratic umbrella for the opposition instead of monopolisation of power,''he said.