Syrian regime forces battling the "Islamic State of Iraq and the Levant" (ISIL) in the northern province of Aleppo have neared a key water pumping station and an airbase, AFP reported Tuesday (March 7th).

Al-Khafsah pumping station provides the water supply for Aleppo, and residents of the regime-held city have been without mains water for some 50 days since ISIL cut it.

"Regime forces are now on the outskirts of the Jarrah military airport and the town of al-Khafsah and the water pumping station," the Syrian Observatory for Human Rights said.

"There are now no villages left between regime forces and the town of al-Khafsah or the town of Deir Hafer," the Observatory said, referring to two ISIL-held areas.

A regime security source confirmed the army had made "significant progress" in the east of Aleppo province, seizing 20 villages and areas on Monday and nearing "the outskirts of al-Khafsah, and the west bank of the Euphrates river".

The regime offensive in Aleppo province has involved heavy air strikes and shelling and prompted an exodus of civilians.

The UN says at least 26,000 have fled since February 25th, with many heading towards the town of Manbij and surrounding villages, which are held by the Syrian Democratic Forces (SDF).