U.N. Special Envoy for Syria Geir Pedersen said on Monday that he would meet foreign ministers from Turkey, Iran and Russia in Geneva on Tuesday, a day ahead of the first meeting of Syria's Constitutional Committee.

Turkey's Mevlüt Çavuşoğlu, Iran's Mohammad Javad Zarif and Russia's Sergei Lavrov are due to meet in the Swiss city before the 150-member Syrian panel convenes under U.N. auspices.

"We do believe that the fighting going on is just another proof of the importance to get a serious political process under way that can help sorting out the problems in all of Syria, including the northeast and also Idlib," Pedersen told in a news conference.