Moderate opposition groups on Thursday took control of Saraqib, a strategic district in Syria's restive Idlib province, from the Assad regime forces.
This comes after these groups on Monday took another strategic village, al-Nayrab in Saraqib, a gateway to Idlib.
In September 2018, Turkey and Russia agreed to turn Idlib into a de-escalation zone in which acts of aggression are expressly prohibited.
But more than 1,800 civilians have been killed in attacks by regime and Russian forces since then, flouting both the 2018 cease-fire and a new one that started on Jan. 12.
More than 1.7 million Syrians have moved near the Turkish border due to intense attacks over the past year.
Attacks by the regime and its allies have also targeted Turkish soldiers on a peace mission in the region in recent weeks.
Turkey remains the country with the most refugees in the world, hosting more than 3.7 million migrants since the start of the Syrian civil war in 2011.