The first day of Syria peace talks in Kazakhstan hit a snag as direct negotiations between opposition and the regime looked unlikely, and as delegates sparred over details of a nationwide truce.

Representatives of the Syrian regime and opposition on Monday traded barbs over interpretations of a ceasefire brokered by Russia and Turkey in late December, as their respective regional backers met behind closed doors to keep the meeting on track.

The Russia-Turkey organized meeting in Astana is aimed at strengthening a nationwide ceasefire that has largely held despite pockets of violence across the country, and paving the way towards UN-led political negotiations in Geneva on February 8.

The talks mark the first time the Syrian opposition is represented solely by representatives of armed groups.

Opposition leader Yahiya al-Aridi complained that the Syrian regime had not demonstrated serious commitment to the ceasefire, arguing there should be "clarity" before direct negotiations.

"If there is seriousness in making these talks lead to something substantial, formality won't be that important," Aridi told Al Jazeera.

But as delegates exited closed-door talks to trade jabs via dueling press conferences, the crux of the meeting may have been happening elsewhere.

Syria analyst with the International Crisis Group Noah Bonsey said that any potential "impact" from the Astana talks is "more likely to come as a result of the trilateral talks between Iran, Turkey and Russia than it is from any direct exchanges between the Syrian delegations".

"We're sitting on the sidelines of talks meant to be between the Syrian government and the opposition, but the main event is what is happening in the trilateral talks," he told Al Jazeera.

"Between Turkey, Russia and Iran you have tremendous leverage and military weight on the ground in Syria. If they make progress in adjusting the ceasefire that has already been agreed ... that could have major military ramifications."

Russia, whose 2015 military intervention in Syria was crucial in shifting the tides of the war in favor of the regime, and Turkey, a prominent backer of the opposition, were key forces in establishing the current ceasefire and bringing the opposing sides to Astana.

But diplomatic sources close to the opposition told Al Jazeera that the role of Iran, a key ally of the regime in Damascus and backer of thousands of allied militia forces on the ground, has been problematic for the opposition within the talks.

The opposition delegation was reportedly hesitant to be seen sitting at the same table as the Iranian delegation and was angry that Iran could be named as the third guarantor - in addition to Russia and Turkey - in strengthening the ceasefire.

In separate press statements, officials from both sides made contrasting claims over whether Jabhat Fateh al-Sham, is present in Wadi Barada.

The strategic area in rural Damascus is home to the capital's main water source. Recent violence there has threatened the fragile truce.

PHOTO CAPTION

A car is parked in front of Rixos President Hotel, the venue that hosts Syria peace talks, in Astana, Kazakhstan, January 23, 2017. REUTERS

Al-Jazeera