An important Syrian government supply route to Aleppo was shut for a second day on Tuesday because of an Islamic State attack, the Syrian Observatory for Human Rights said.
A rebel fighter told Reuters the Islamic State assault on the road linking Aleppo to government-held cities further south had relieved pressure on insurgents confronting Syrian government forces backed by Russian air strikes in Aleppo.
A Syrian military source told Reuters army operations were continuing in order to repel the Islamic State assault on the road linking government-held cities of western Syria with Aleppo.
Observatory Director Rami Abdulrahman told Reuters: "The clashes are ongoing, the regime recovered four of seven (lost positions). It is still cut."
The Syrian government has been using the desert road running through the villages of Khanaser and Ithriya to reach Aleppo because rebels still control the main highway to the city.
