Syrian government’s chief negotiator, Bashar Ja'afari said President Bashar al-Assad’s future is not up for discussion at peace talks, undermining the already bleak prospects for reviving the United Nations (UN) led negotiations.

Last week, in an internet message to fighters on the ground, chief negotiator of the opposition, Asaad al-Zoubi said they would not be ready discuss to any proposal other than the transfer of power from Assad to a transitional body.

That was not his only message to the rebels; Zoubi also commented that there was a limit to how long the negotiations, which are now postponed, would last. He also urged rebels to retaliate against government fire.

Despite the cease fire set by the United States and Russia, the government uses the opportunity to advance further in rebel-controlled areas and apparently there is no progress on the key opposition demand for political transition without Bashar al-Assad. Those two significant step backs put the whole process on the verge of collapsing.

Until now there has been no deadline on the part of the opposition as to when they would leave the peace talks. However, an anonymous source who is a senior opposition figure said to Reuters that the pressure is growing for a speedy decision to leave.

Bashar Ja'afari, Assad’s main negotiator, speaking to Lebanese TV station al Mayadeen, said his team is pushing for an expanded government.

“In Geneva we have one mandate only to arrive at an expanded national government only, this is our mandate … this is the goal we strive to achieve in the Geneva peace talks” Ja'afari said. He added that these views also echoed UN Syria mediator Staffan de Mistura.

The opposition categorically rejects this proposal. After 5 years of war against Assad, they were clearly infuriated Mistura’s suggestion that Assad could stay on in power in a symbolic role.

Ja’fari however said President Assad’s fate is not a matter that could be decided in peace talks. “This matter (the presidency) does not fall under the jurisdiction of Geneva … this is a Syrian-Syrian affair, Security Council or no Security Council” he said, indicating no shift on the regime’s position, as it enjoys firm support from Russia and Iran.

Meanwhile, fighting near Aleppo has been escalating for two weeks, mostly to the south of the city where government forces have been attacking rebels’ positions.

“We might suspend [our participation in] the talks if things carry on this way, and then there will be no prospect for any political solution” High Negotiations Committee (HNC) member Abdulhakim Bashar told AFP, as a renewed flare-up in violence in Aleppo killed another 22 civilians.

The opposition is now questioning Assad’s regime will for a political solution altogether, taking into account the surge of violence. They argue that if Damascus was serious about moving forward a UN backed political process they would bring a transitional governing body with full executive powers without Assad.

A UN Security Council resolution in December called for the establishment of “credible, inclusive and non-sectarian governance”, a new constitution, and free and fair elections within 18 months, which as this point seems unlikely. The regime organized its own parliamentary elections only a few days ago. Several states, including Germany who refused to recognize their results, doubted the conditions under which the elections were held, in the parts of Syria that are controlled by Assad, without the participation of the opposition.

Ja'afari, speaking on behalf of the regime, accused the Western-backed opposition of seeking to bring about a collapse of the country and replicate the chaos seen in Iraq and Libya after Western military intervention brought down long severing authoritarian rulers.

More than 250.000 people have been killed in the five-year-old conflict; almost 11% of Syria’s pre-war population has been killed or injured.