US Secretary of State Rex Tillerson has agreed with several of his European and regional counterparts on a joint vision for a political solution in Syria, including limiting the president’s authorities and “drawing a line” between him and the prime minister, Western diplomatic sources told Asharq Al-Awsat on Thursday. The document, which calls for “a neutral” security apparatus and the withdrawal of “foreign militias” from the country, also suggested that UN Special Envoy to Syria Staffan de Mistura “exerts pressure” on the Syrian regime and opposition delegations to push them onto “holding compulsory talks on constitutional reforms, place new criteria allowing the UN to monitor the upcoming polls, and create a safe and objective environment in Syria that allows holding elections without fear.” For his part, UN Secretary-General Antonio Guterres sent on Thursday to Russian Foreign Minister Sergei Lavrov a letter that includes a set of conditions for the UN to attend the two-day Sochi congress on Syria next Monday. One of the conditions is for the Syrian government delegation to “constructively engage” in the Vienna peace process that kicked off Thursday with a meeting between de Mistura and representatives from both delegations. However, there are other elements set by Guterres as a condition for the UN participation in the Syrian National Dialogue Congress. The Secretary General calls for the formation of a constitutional committee with representatives from the Syrian government, the opposition and other parties, in addition to agreeing on the authorities of this committee as part of the Geneva process. The constitutional committee should supervise the national dialogue and formulate a new constitution, Guterres says. The UN chief also demands that the Sochi congress be held once and that it supports the Geneva peace process. Furthermore, he calls on Bashar “Assad’s commitment to approve a new constitution for holding parliamentary and presidential elections under UN supervision and in line with Resolution 2254.”