The Syrian government has rejected the UN envoy's call for elections to be held in the next 18 months, adding that the issue of the presidency remained a "red line" ahead of fragile peace talks in Geneva on Monday.
Staffan de Mistura, the UN envoy for Syria, told Russia's RIA Novosti state news agency on Friday that one of the main topics at the negotiations would be the implementation of UN-monitored presidential elections within 18 months.
Yet, Walid al-Muallem, the Syrian foreign minister, said on Saturday that the government delegation would reject any attempt to include presidential elections on the agenda.
"Neither he [de Mistura] nor anyone else, whoever they may be, has the right to discuss presidential elections. This right is exclusively for the Syrian people," Muallem told a news conference in Damascus.
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He added that the government delegation to the talks will wait no more than "24 hours" for the opposing side to arrive.
"We will not talk with anyone who wants to discuss the presidency ... Bashar al-Assad is a red line and is the property of the Syrian people," Muallem said.
The main opposition bloc, the Riyadh-based High Negotiations Committee (HNC), has repeatedly called for Assad's departure at the start of any transitional period.
"If they continue with this approach, there is no reason for them to come to Geneva," Muallem said.
'Assad should go'
Yet, Mozner Akbik, a representative with the Syrian opposition, told Al Jazeera that Assad has to leave as part of the political transition.
"The Geneva communique and various UN Security Council resolutions call for a genuine political transition of power in Syria. If this does not happen, the Syrian problem cannot be solved," Akbik, a member of the Syrian National Coalition, said from Cairo.
"This means that Assad has to go. If Assad does not go, I don't think the war will end."
Both the government and the HNC have agreed to participate in the fresh round of indirect talks in Geneva.
The last round of UN-mediated talks in the Swiss city collapsed in February.
At the time, the HNC delegation arrived in Switzerland around 36 hours after the government, but waited another two days to head to the UN headquarters.
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The Syrian opposition's Akbik told Al Jazeera there was no reason to doubt that the opposition would contribute to the talks.
"The opposition always participated and seriously engaged in Geneva talks twice. And this is what we will do this time as well," he said.
UN peace envoy Staffan de Mistura said the talks would cover the formation of a new government, a fresh constitution, and UN-monitored presidential and parliamentary elections within 18 months.
He also said that the possibility of federalism had not been taken off the table.
"All Syrians have rejected the division [of Syria] and federalism can be discussed at the negotiations," de Mistura told Al Jazeera.
However, Foreign Minister Muallem said a federal division of Syria was not an option, adding that the negotiations would aim to form a "unity government" which would then appoint a committee to either write a new constitution or amend the current one.
"Then we will have a referendum for the Syrian people to decide on it," he said.
Fighting across parts of Syria has decreased after the regime and rebels agreed to a landmark ceasefire brokered by Washington and Moscow, but both sides have repeatedly accused each other of violations.
Source: Al Jazeera and agencies