Syria's ambassador to the United Nations says any discussion of a transition in power in the war-torn country is off the table as peace talks get under way on Monday in Geneva.
Bashar Jaafari, leading the government delegation to Switzerland, said in an interview with Syrian state TV late on Sunday that discussions on removing President Bashar al-Assad by the opposition were an attempt to derail the so-called proximity talks before they even begin.
"It's premature to talk about a transitional period for Syria," Jaafari reiterated. "The talk about such an existential issue that defames a symbol of the Syrian republic sovereignty [Assad] is firstly a rush to fail the talks and the efforts of the UN envoy to make this new round of talks successful."
Syria's main opposition group, the High Negotiations Committee, or HNC, has announced it expects Geneva discussions to include Assad's departure and a timeframe for elections.
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Speaking after talks with European allies in Paris on Sunday, US Secretary of State John Kerry said Russia and Iran would need to press their Syrian ally to show that Damascus is "living up to" what had been agreed on the peace talks' agenda.
"President Assad is singing on a completely different song sheet and sent his foreign minister out yesterday to try to act as a spoiler and take off the table what President Putin and the Iranians have agreed to," Kerry said.
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Monday's talks will coincide with the fifth anniversary of a war that has killed more than 250,000 people, created the world's worst refugee crisis, and allowed the expansion of the Islamic State of Iraq and the Levant (ISIL, also known as ISIS).
Al Jazeera's Diplomatic Editor James Bays, reporting from Geneva, said UN envoy Staffan de Mistura has stated that he wants negotiations to focus on "substantive issues", including a new constitution and UN-monitored elections.
"I think what is important this time around is that we seem to be getting to the key crunch issue - the future role of President Assad and those close to him," Bays said.
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De Mistura told Al Jazeera that under the current "cessation of hostilities", there is a higher chance than ever of achieving a political solution in Syria.
The Riyadh-based High Negotiations Committee, however, has repeatedly called for Assad's departure in order for peace to take hold.
"We consider that the transitional period begins with the departure of Bashar al-Assad - or his death. It cannot be a stage where this regime, or the head of this regime, continues to be in power," said Mohammed Alloush, HNC's senior negotiator.
The talks on Monday are part of the first diplomatic push since the Russian air force intervened in September to support Assad, tilting the war in his favour and helping the government reclaim significant areas in the west.
Source: Al Jazeera and agencies