The delegation of the Syrian government to the international conference on Syria planned for next month was formed while that of oppositions was not yet, said the special envoy for Syria Friday.

Lakhdar Brahimi, the United Nations-Arab League Joint Special Representative for Syria, made the remarks at a press conference after the trilateral preparation talks on the Syria peace talks between the UN, Russia and the United States and meetings with five permanent members of the UN Security Council, Syria's neighboring countries, the European Union (EU) and the League of Arab States held Friday.

Brahimi said the Syrian government has officially informed them that their delegation have been formed, and were expected to publicize the name list soon.

As for the Syrian oppositions, the envoy said they met representatives with the Syrian National Coalition and were notified that the coalition were reaching out to others inside and outside Syria, but they would not form their delegation before Dec. 27.

He stressed again that the delegation need to be "credible", hoping it to be as representative as possible.

Brahimi appealed for the warring parties in Syria to demonstrate their devotion to the upcoming peace talks.

"We hope that now that we have a date for the conference, the parties will unilaterally take a number of decisions as measures to indicate that they are coming to Geneva to end this conflict," he said.

Other participants to the long-delayed Syria peace-talk have been decided except Iran, whose presence is still undecided.

Brahimi said the United States was still unconvinced that Iran's participation would be "the right thing to do", adding there would be further discussions on the presence of Iran to see if an agreement was possible to be achieved.

In addition to delegates of the UN, P5, the League of Arab States, the EU, and the Organization of Islamic Cooperation, 26 countries including Iraq, Jordan, Lebanon and Turkey, the four main host to Syrian refugees, Arabic countries in the region such as Saudi Arabia, Qatar, the United Arab Emirates, and Egypt, as well as western countries like Germany, Canada and Denmark, will be present at the conference.

Brahimi reiterated that the conference will be held without any prior conditions, saying that the duration of the conference was open-ended.

The mediator confirmed that the conference set to be held on Jan. 22 in Montreux, a lakeside city in southwest Switzerland, will be launched and presided over by UN Secretary General Ban Ki-moon, who would provide a summary over the meetings at the end of the day.

In the wake of the high-level talks, delegates of the Syrian government and the oppositions will start negotiating with the presence of UN back in Geneva.

The Action Group meeting on Syria in Geneva was held in June, 2012, with the involvement of ministers, during which participants agreed upon a set of principles and guidelines that ushered the way for a Syrian-led transition from conflict to peace.

In early May, 2013, the United States and Russia agreed to sponsor another international conference in Geneva to end the conflict.

Since then, trilateral preparation meetings between the UN, Russia and the United States for the International Conference on Syria were held in Montreux respectively in June and November, with the previous held on Nov. 25.

The upcoming International Conference on Syria, usually dubbed as Geneva II conference, is different from Geneva I, and the Syrians, including the government and the oppositions are going to be well represented, according to Brahimi.

UN statistics showed that, the over 30-month conflict in Syria led to over 2.3 million people registered Syrian refugees in the region and millions more people displaced internally in the war-torn country.

The number of Syrian refugees would rise as high as 4.1 million by the end of 2014 based on current trends, figures indicated.