Syrian opposition says Assad must go

The demise of Syrian President Bashar al-Assad is a prerequisite to end Syria's civil war, the opposition party negotiator says.

Syrian President Bashar al-Assad's harsh response to dissent is said to have sparked the civil war. Source: AAP

Syrian opposition negotiator Mohamad Alloush says Syria's political transition can only start once Bashar al-Assad is no longer president of Syria.

"We consider that the transitional period starts with the fall of Bashar al-Assad or his death," he told reporters in Geneva on Saturday, where a round of peace talks is due to begin on Monday.

"There's no possibility to start this period with the presence of this regime or the head of this regime in the power."

He described as "worthless" a statement by Syrian Foreign Minister Walid al-Moualem earlier on Saturday that the presidency was not up for discussion at the talks.