On Wednesday, Salim al-Muslit, the spokesman of the so-called High Negotiations Committee (HNC) that includes militant groups and opponents of President Bashar al-Assad, said he supported direct talks between the HNC and the Syrian government.
The Kazakh Foreign Ministry says the talks, to be held in preparation for United Nations -brokered Syria negotiations in Geneva, will be postponed until Thursday.
The Astana initiative has left the West on the sidelines of the latest push to end the war in Syria that has claimed more than 300,000 lives since 2011.
"That is the agenda and we will not change it, otherwise we open up a Pandora's box", said de Mistura, whose attempts to apply the same agenda to talks past year drew a sharp rebuke from Damascus.
He also said de Mistura's absence had been expected.
Turkey, which has been a major supporter of the rebellion against Assad, has jointly brokered with Russian Federation a ceasefire to pave the way for the talks. The communique said it should be formed on the basis of mutual consent.
Mohammad Alloush, of the Islam Army rebel group, said he will insist on discussing the December 30 cease-fire at the talks in the Kazakh capital, Astana, which have been postponed to tomorrow. The regular session of the worldwide group on the settlement of the Syrian conflict in Astana, due on February 15, is postponed and will be held on February 16, the Ministry of Foreign Affairs of Kazakhstan said, reports TASS.
Syria's rebels won't begin negotiating a political settlement with the government until measures are taken to bolster a flagging cease-fire and address urgent humanitarian concerns, the head of the opposition delegation to planned talks in Kazakhstan told The Associated Press today.