The UN is calling for a “firewall” around the Syria constitution drafting process, after diplomatic talks for the conflict-torn country were postponed over Russian demands reportedly linked to its war in Ukraine. The UN Special Envoy for Syria, Geir Pedersen, had been set to host a ninth round of talks in Geneva to discuss a new Syrian constitution this week. But he was forced to postpone after Moscow raised issues over the venue, reportedly insisting that Switzerland, which has imposed sanctions over the Ukraine war, is not neutral. Spokeswoman Jenifer Fenton told reporters in Geneva that Ped…