Speaking to reporters at the Arab League headquarters in Cairo on Tuesday, Brahimi said that the UN was working to organize the conference in a manner that would lead to the best outcome for the Syrian people.

"The Syrian people are building great hopes on the conference,” he said, adding that “The United Nations is working to organize the conference in the best way possible."

"The Geneva 2 conference is a great opportunity, and we hope that the brothers in Syria and the regional and international parties will cooperate to make it succeed," Brahimi said.

He added that "There are many problems in the preparation for this conference, the first of which is the formation of the delegations of the Syrian government and the opposition."

European diplomatic sources said the Syrian government has submitted the names of five potential negotiators for the conference.

Russia, which proposed the talks along with the US, has repeatedly said Iran should take part in the conference.

US Secretary of State John Kerry is due to discuss current planning for the conference at a meeting of the so-called "Friends of Syria" in Jordan on Wednesday.

Syria's opposition is also due to meet in Istanbul on Thursday to announce its stance on the conference.

The first Geneva talks, which was held under the chairmanship of former mediator Kofi Annan last June, calls for a political process to end the crisis in Syria.

Syria has been gripped by unrest for over two years, and many people, including large numbers of Syrian soldiers and security personnel, have been killed in the foreign-sponsored militancy.

Syria’s President Bashar al-Assad said on May 18 that militants from 29 different countries were fighting against the government in different parts of the country.