In the first concrete results from talks this week on ending Syria's conflict, the United Nations said Thursday the warring sides had agreed to set up expert committees to discuss "constitutional issues." Representatives of Syria's government and opposition High Negotiations Committee (HNC) are in Switzerland for the sixth round of UN-backed peace negotiations, but there has been no sign of progress. On Thursday, UN mediator Staffan de Mistura's office declared a first tangible step: a series of separate meetings with the government and HNC delegations to discuss "legal and constitutional issues of relevance to the intra-Syrian talks." The announcement appeared to be watered-down version of a previous UN proposal towards a new constitution. A new constitution for Syria is one of four separate topics or "baskets" on the agenda at the talks, alongside governance, elections and combating "terrorism." By Thursday, however, government delegation head Bashar al-Jaafari said his team had "not discussed any baskets yet." Speaking to journalists shortly after the UN's announcement, Jaafari seemed to play down how much the expert meetings would push the constitutional process forward. "The work of these experts will have nothing to do with the constitution... They will not take decisions," Jaafari said. The Syrian diplomat described the UN's earlier plan as "too ambitious." That team would have been responsible for finding "specific options for constitutional drafting," according to a copy of the document seen by AFP. The talks, which opened on Tuesday, were at risk of being overshadowed by months of parallel negotiations in the Kazakh capital, Astana. Observers said de Mistura would be scrambling to match the Astana track's momentum. The HNC held its own meetings with de Mistura on Thursday, focused on "political transition and the constitutional framework," spokesman Yehya al-Aridi told AFP. The opposition has continued to demand that Syrian President Bashar al-Assad step down as part of a political transition process, which the government sees as a non-starter.