Turkey's Foreign Minister Mevlüt Çavuşoğlu said on Sunday that the Syrian opposition was free to leave peace talks in Geneva if its demands were not met."We asked the opposition that they can put their conditions to start the negotiations and continue the negotiations. They can leave anytime if they are not implemented," Çavuşoğlu told a news conference in the Saudi capital Riyadh."We back demands for a truce and for sending humanitarian aid" to besieged towns in Syria as requested by the opposition." he added.The High Negotiations Committee (HNC), which represents the main body of the Syrian opposition, had demanded a halt to attacks on civilian areas, the release of detainees and a lifting of blockades if it is to attend the indirect talks with the regime delegation. The measures were mentioned in a U.N. Security Council resolution approved last month that endorsed the peace process for Syria.Regarding the demands, the opposition delegation met at a Geneva hotel with U.N. special envoy to Syria Staffan de Mistura for the first time on Sunday, demanding President Bashar Assad's government be made to comply with the U.N. resolution on humanitarian aid and human rights.Previously, the opposition delegations that met in Riyadh on Thursday decided not to attend the talks in Geneva until an agreement was reached to end airstrikes and bring aid to besieged towns.Although the talks started on Friday without the HNC, later on it decided to attend, according to the Al-Arabiya Al-Hadath news channel on the same day.

 "The HNC decided to participate in the Geneva talks after receiving American and United Nations guarantees," the news channel said.

 The delegation arrived in Switzerland on Saturday evening to join the talks with 17 negotiators and 25 other representatives.