Syria's opposition says it will attend peace talks that are set for next Monday, but has downplayed the chances of reaching agreement with the Syrian government.
The UN-brokered talks, which coincide with the fifth anniversary of the start of the conflict, will take place in Geneva just over two weeks after a ceasefire agreement took effect which has reduced violence but not halted the fighting.
The High Negotiations Committee said in a statement it would attend as part of its "commitment to international efforts to stop the spilling of Syrian blood and find a political solution".
The upcoming talks are to focus on new governance, a constitution and elections, UN envoy Staffan de Mistura said.
The HNC said it would focus on the establishment of an interim governing body with full executive powers and would insist on Syria's territorial integrity.
HNC coordinator Riad Hijab said it was "concerned with representing the just cause of the Syrian people... and investing in all available chances to alleviate the Syrian people's suffering."
"We know that they [the government] are committing crimes, and that they are preparing an air and ground escalation in the coming period," he said, without elaborating.
Hijab said the Syrian government was trying to thwart the political process.