Damascus, May 30 (IANS): The chief negotiator of Syria's main opposition umbrella group has resigned over what he called the failure of peace talks.

Mohammed Alloush, from the High Negotiations Committee (HNC), on Sunday said the talks had not brought a political deal or eased the plight of Syrians in besieged areas, BBC reported.

"The three rounds of talks were unsuccessful because of the stubbornness of the regime and its continued bombardments and aggressions against the Syrian people," Alloush said.

The Saudi-backed HNC has for months expressed its frustration about the progress of the Geneva talks.

It has suspended its involvement in the UN-brokered "proximity" negotiations with a Syrian government delegation in Geneva in April.

No date has been set for a resumption.

A nationwide truce between rebel and government forces brokered by the US and Russia is officially still in place, but is frequently violated.

More than 250,000 Syrians have been killed and about 11 million people have been forced from their homes during the civil war, which began with an uprising against President Bashar al-Assad five years ago.