Egyptian Foreign Minister Nabil Fahmy has invited Syrian opposition groups to Cairo for talks on unifying their disparate positions.

The Syrian opposition should unite their views to create "real policies" that pave the way for a "civil state for all Syrians," Fahmy said.

During his opening speech at the Geneva II talks Fahmy said peace would only be reached through a political solution that takes Syria from "a state of conflict to consensus," state news agency MENA reported.  

He called on the Syrian government to end the "tragedy of the Syrian people" and prevent the "deterioration of the regional situation which is heading towards an ethnic clash."

"Egypt will work on providing the necessary support for negotiations to enhance their chance of success," Fahmy concluded.

World powers urged Syria's warring sides to seize a "historic" opportunity as they gathered in Switzerland on Wednesday for a peace conference that began with bitter exchanges, AFP reported.

Meeting for the first time since the start of the conflict in March 2011, the two sides could not be further apart at the Geneva II conference in Montreux on the shores of Lake Geneva.

There were few early signs of compromise as the most serious bid yet to end three years of bloodshed began, with Syrian Foreign Minister Walid Muallem dubbing the opposition "traitors" and foreign agents.