Syrian opposition groups meeting in Spain say they oppose all negotiation with President Bashar al-Assad's government unless it is aimed at his giving up of power.
About 80 opposition representatives from inside and outside Syria concluded a two-day meeting on Tuesday, saying Assad would neither form part of any transition government nor have any role in Syria's future.
Moaz al-Khatib, former chief of the Syrian National Coalition, said a decision on whether the opposition groups would take part in a conference in Geneva on Syria*s future, proposed by Russia and the US, would be taken within two weeks.
The groups oppose Assad representatives taking part in the meeting.
Al-Khatib resigned last week, citing the failure of the international community to stop the conflict as the reason.
Pressed back by army advances, Syria's opposition is under international pressure to enter into dialogue with Assad's government.
More than 80,000 people have been killed in the conflict, according to the UN, and 1.5 million people have fled the country since the uprising began in March, 2011.
Among the Madrid meeting's aims was "to facilitate dialogue between the various movements in the Syrian opposition, thereby aiding its cohesion and its future capacity to ensure unity, stability and democracy in Syria," the Spanish foreign ministry said in a statement.
"The international effort currently under way to this end requires the forming a strong, unified and diverse opposition capable of representing a common front."
Spain in November recognised the coalition as the Syrian people's legitimate representative, along with several Western and Arab powers.
Spanish Foreign Minister Jose Manuel Garcia-Margallo said last month that Madrid backed the formation of a national unity government in Syria as a way out of the two-year conflict.
Before resigning, Khatib had faced criticism of his perceived overly moderate position towards the Assad government.
He was pressured to step down after leading members of the coalition berated him for offering Assad a deal, and after the
bloc went ahead with steps to form a provisional government against Khatib's explicit wishes.