Turkey and Syrian Kurdish forces are both accusing each other of violating a temporary ceasefire agreement in northern Syria.
The US announced on Thursday it had brokered a five-day pause in fighting to allow Kurdish forces to withdraw.
Turkey views the Kurdish forces as terrorist groups and wants to create a “safe zone” buffer by its border.
Despite the ceasefire, some sporadic violence has continued – particularly around the border town of Ras-al-Ain.
Turkey’s defence ministry accused Kurdish forces of carrying out 14 “provocative” attacks in the last 36 hours, mostly in the town, but insisted Turkish forces were fully abiding by the agreement.
However, the Kurdish-led Syrian Democratic Forces (SDF) have accused Turkey of violating the ceasefire.
They also accuse Turkish troops of failing to create a safe corridor for the evacuation of civilians and wounded people from the besieged town.
On Saturday the SDF urged US Vice-President Mike Pence, who helped broker the ceasefire, to pressure Turkey to allow the passage of civilians.
“Despite the constant communication with the American side and the promise made by them to solve this problem, there has not been any tangible progress in this regard,” the SDF said in a statement.
The UK-based Syrian Observatory for Human Rights (SOHR) allege that deliveries of humanitarian aid have also been prevented from entering Ras-al-Ain.
The war monitor said Friday that the civilian death toll from the Turkish operation had now risen to 86.
Between 160,000 and 300,000 people have reportedly fled their homes since the offensive started ten days ago.
What prompted the offensive?
Turkish forces first launched their assault on 9 October, following an announcement US troops would withdraw from the Syria-Turkey border region.
Turkish President Recep Tayyip Erdogan’s operation aims to push Kurdish fighters away from northernmost Syria and create a 20 mile (32km) “safe zone” for resettling up to two million Syrian refugees currently in Turkey.
The goal was to push back a Kurdish militia group – the People’s Protection Units (YPG) – that Turkey views as a terrorist organisation.
Turkey had hoped to resettle up to two million Syrian refugees in the border area, but critics warned that could trigger ethnic cleansing of the local Kurdish population.
Since the offensive was launched, President Donald Trump has been accused by some, including senior Republicans, of abandoning a US ally. The SDF – a group dominated by the YPG – fought alongside the US against the Islamic State (IS) group in Syria.
There has been growing international concern about possible war crimes committed by Turkey and allied militias during the offensive.
Amnesty International says it has gathered “damning evidence” of war crimes and other violations by their side and the United Nations has called on Turkey to investigate the allegations.
Unconfirmed reports have also emerged that Turkish-allied forces have used white phosphorus, a chemical weapon which causes bad burns, in Syria.
The Organisation for the Prohibition of Chemical Weapons (OPCW) said it was aware of the claims and was gathering evidence.
What is the latest with the ceasefire?
The pause in hostilities followed talks in the Turkish capital Ankara between Mr Erdogan and Mr Pence on Thursday.
President Trump celebrated news of the ceasefire and claimed the pause in hostilities would lead to “millions of lives” being saved. He remained optimistic in comments made on Friday, despite reports the ceasefire was failing to hold.
SDF spokesman Mustafa Bali tweeted on Friday morning to allege that Turkey was breaking the ceasefire near Ras al-Ain.
“Despite the agreement to halt the fighting, air and artillery attacks continue to target the positions of fighters, civilian settlements and the hospital,” he wrote.
President Erdogan dismissed reports of continuing clashes on Friday as “misinformation” but international news media recorded explosions in Ras al-Ain during the morning.
The SOHR said Saturday that the SDF had not yet started to pull back from the border region.
Local Kurdish media are reporting that five civilians and 13 Kurdish fighters in Ras-al-Ain have been killed since the ceasefire began, but the BBC has not been able to independently confirm that.