Government troops have seized swathes of northern and eastern territory in the last two weeks from the Kurdish-led Syrian Democratic Forces in a rapid turn of events that has consolidated President Ahmed al-Sharaa's rule.
Sharaa's forces were amassing around a last cluster of Kurdish-held cities in the northeast earlier this week when he abruptly announced a ceasefire, giving the SDF until Saturday night to come up with a plan to integrate with Syria's army.
The deadline is aimed at pushing through a sweeping deal agreed on January 18 that would transfer the semi-autonomous institutions run by Kurdish forces in the northeast over the last decade to the central state, something the SDF had resisted over the last year.
The agreement also stipulates that the government would take control of a string of SDF-run prisons and detention camps holding fighters and civilians linked to Islamic State, the ultra-conservative Sunni Islamist militant group that the SDF fought for years with US backing.
This week, one prison and one detention camp fell to the government after chaotic withdrawals by the SDF, in which some IS-linked individuals briefly escaped.
Seeking to avoid a security breach, the government negotiated the pull-out of Kurdish fighters from the al-Aqtan prison in the northern province of Raqqa overnight.
A senior Syrian government official told Reuters on Friday the negotiations over al-Aqtan gave hope that Saturday's deadline would yield a political solution instead of renewed fighting.
However, he said the government had not yet received a response from the SDF on its integration plan or its candidate for deputy defence minister, a post for which Sharaa had asked the SDF to nominate someone.
SDF sources said on Friday the deadline for their response could be extended but the Syrian official said there was no discussion of an extension at this time.
Despite hope for a negotiated resolution, both sides have ramped up military preparations.
Syrian military officials say they are readying forces for a fight and Reuters reporters have seen army vehicles and buses of fighters arriving near the Kurdish-held city of Hasakeh, where Kurdish forces have also reinforced positions.
Senior officials from primary mediator the United States and France, which has also been co-ordinating ceasefire talks, have urged Sharaa not to send his troops into remaining Kurdish-held areas, diplomatic sources told Reuters.
"We are calling on the Syrian authorities to assume their full responsibility in protecting all civilians, including Kurdish civilians," French foreign ministry spokesman Pascal Confavreux said.
The US, which long backed the SDF but now views Sharaa as its primary partner in Syria, has been helping transfer detained IS fighters from Syria to Iraq.
The SDF withdrew on Tuesday from al-Hol, which along with another camp, Roj, houses 28,000 civilians, mainly women and children who fled IS strongholds as the group's self-proclaimed caliphate collapsed.
They include Syrians, Iraqis and 8,500 citizens of other countries.
The United Nations refugee agency UNHCR was able to access al-Hol camp on Friday with Syrian government officials and established contact with some camp residents, deputy UN spokesman Farhan Haq said.
"Essential supplies have also resumed. Trucks carrying bread entered the camp today, facilitated by UNHCR following a three day interruption caused by the volatile security situation inside the camp. In addition, water trucking services organised by UNICEF ... were delivered yesterday, helping to partially restore access to basic services for the camp population," Haq said.
In a bid to improve ties with Kurds in Syria, Sharaa issued a decree on January 16 that designates Kurdish as a national language alongside Arabic.
