Kazakhstan's Foreign Ministry announced it is delaying by one day talks on the Syrian civil war that were due to start on February 15.
Russia, Iran, and Turkey were to be involved in the talks, which were also to include delegations from the Syrian government and rebel groups. Some of those delegations have already arrived in the Kazakh capital, Astana, for the talks.
United Nations Syria envoy Staffan de Mistura has also been invited.
The postponement came as Russian jets pounded rebel-held areas of the Syrian city of Deraa on February 14 for a second day in the first such intensive bombing campaign in months, with at least 30 Russian sorties reported.
Rebel groups on February 12 stormed the Manshiya district in a battle they dubbed "Death rather than humiliation," vowing to obstruct the Syrian Army's attempts to capture a strategic border crossing with Jordan.
The opposition fighters include both the moderate Free Syrian Army and a newly formed Islamic alliance -- Tahrir al Sham -- spearheaded by a faction affiliated with Al-Qaeda that was excluded from a cease-fire between other parties to the conflict.