Government forces seized control of a highway in northwest Syria for the first time since 2012 on Tuesday, a war monitor said, as talks ended between Turkey and Russia on stopping clashes that killed 13 Turkish soldiers in a week.
The M5 highway is the main road between Aleppo and the capital Damascus and runs through to Deraa in southern Syria.
Syrian forces seized the entire length of the M5 after driving rebels from their last foothold on the road, the Syrian Observatory for Human Rights, a British-based war monitor, said.
Those forces, backed by Russia and Iran, took control of the highway after capturing a western suburb of Aleppo from insurgents as the government intensified its campaign to capture the last rebel-held stronghold in Syria's nearly nine-year-old war.
Last week, government troops recaptured Saraqeb, a strategic crossroads town where the M5 intersects with a main west-east highway.
The latest advances by Syrian President Bashar al-Assad's forces come after 13 Turkish troops were killed in the northwestern Idlib region over the past week, prompting some of the most serious confrontations between Ankara and Damascus.