Geneva, Feb 3 () - Syria’s main opposition group said Feb. 2 that it will not attend a planned afternoon meeting with the U.N. special envoy Staffan de Mistura, adding further doubts about the prospects for peace talks in Switzerland.

“There is no meeting with de Mistura” said Farah Atassi, member of the Saudi-backed High Negotiations Committee (HNC).

“We presented the demands that we wanted to demand. At this moment, there is no reason to repeat ourselves with de Mistura,” she told reporters outside of the U.N. headquarters in Geneva.

United Nations spokeswoman Khawla Mattar also confirmed that there would be “no other meetings today” with de Mistura, who met with the Syrian government delegation in the morning of Feb. 2.

The afternoon gathering was to be the opposition delegation’s second meeting with the Swedish-Italian diplomat at the U.N. headquarters.

The announcement followed comments from the government’s chief negotiator Bashar al-Jaafari that formal indirect peace talks had not yet begun.

De Mistura had said Feb. 1 that his first official meeting with the HNC meant that the negotiations were indeed under way.

“The circumstances on the formalities are not yet ready. We are in the preparatory stage before the official launch of indirect negotiations,” Jaafari told reporters after a meeting with de Mistura.

“To prepare the official launch we have to have the presence of the two delegations, but on the other side the delegation has not been finalized,” he added.

Representatives of the HNC - which includes political and militant opponents of President Bashar al-Assad - have warned that they will not negotiate unless the government stops bombarding civilian areas, lifts blockades and releases detainees.

Meanwhile, Turkish Foreign Minister Mevlüt Çavuşoğlu has resumed regular contact with his U.S. counterpart, Secretary of State John Kerry, as Syrian peace talks continue.

Çavuşoğlu has been accompanying President Tayyip Erdoğan during an ongoing Latin America tour that covers Chile, Peru and Ecuador. While in Santiago, the first leg of the tour, Kerry called Çavuşoğlu on Feb. 1 and the two exchanged views on the Geneva peace talks, Turkish diplomatic sources said.

In last ten days, Çavuşoğlu and Kerry have appeared to be in constant contact over the highly anticipated talks.

Most recently, Çavuşoğlu spoke to both Kerry and British Foreign Secretary Philip Hammond on Jan. 29. Earlier, on a visit to Strasbourg to hold talks at the Council of Europe and the Parliamentary Assembly of the Council of Europe (PACE), Çavuşoğlu spoke to both Kerry and Hammond.

On Jan. 24, the Turkish foreign minister spoke to both Kerry and French Foreign Minister Laurent Fabius and discussed the planned talks in Geneva.

On Feb. 2, Syrian government forces have taken several key villages north of the city of Aleppo as they press an advance that could break a long-running rebel siege of two Shiite villages.

Syrian state news agency SANA said government troops backed by pro-regime militants had “restored security and stability to the village of Hardatneen.”

The capture was also reported by the Syrian Observatory for Human Rights, a Britain-based monitor, which said government forces had also seized part of the nearby village of Ratyan.

The advances come after regime forces, backed by Russian air strikes, seized two other villages in the area on Feb. 1.

They bring government troops within five kilometers of the Shiite villages of Nubol and Zahraa, which are under regime control but have been besieged by rebel forces for over two years.

Observatory chief Rami Abdel Rahman said the capture of Ratyan and one smaller village could allow regime forces to effectively break the siege on Nubol and Zahraa, a longstanding government goal.

Meanwhile, U.S. Deputy Secretary of State Tony Blinken spoke to Salih Muslim - the head of the Syrian Kurdish Democratic Union Party (PYD) - about the Syria peace talks and the “continued cooperation in the fight against Daesh in northern Syria,” a spokesman said Feb. 1, using an acronym for Islamic State (IS).

In a telephone call, Blinken reinforced the importance of moving forward the political process for Syria, according to State Department spokesman John Kirby.