The Syrian opposition's chief negotiator in the Geneva peace talks has resigned amid no signs of progress in the peace process.

Mohammed Alloush says he took this step, claiming the international community is not "serious" about reaching a solution for the country's five-year civil war. He says Syrian government forces have continued attacking the opposition and are besieging rebel-held areas, despite the three rounds of negotiations in Geneva.

Alloush also says in his statement, which was released late on Sunday, that the United Nations has not been able to set up a transitional government body for Syria or find a political solution to the crisis.

He says he has handed in his resignation to the High Negotiations Committee.