Up to 500,000 civilians in Mosul are facing a "catastrophic" drinking water shortage, the UN warned on Wednesday (November 30th), as Iraqi forces advance against the "Islamic State of Iraq and the Levant" (ISIL) in the city, AFP reported.

Already suffering from a severe lack of food and electricity, civilians in Iraq's second city are now also running out of drinkable water, said Lise Grande, UN humanitarian co-ordinator in Iraq.

"Nearly half a million civilians, already struggling to feed themselves day to day, are now without access to clean drinking water. The impact on children, women and families will be catastrophic," Grande said.

Weeks of fighting have seen the Iraqi forces surround the city and break into its eastern neighbourhoods, where there have been heavy street-to-street battles with the extremists.

Operations to retake the city have damaged water pipes in recent days and residents in east Mosul say they have resorted to pumping water from wells.

Abdelkarim al-Obeidi, the secretary general of the local civil society organisation Mosul People Gathering, warned of a "humanitarian disaster" in the making.

"The government as well as aid organisations must step up and offer assistance to the people, especially those families forced to drink water from the wells that is not fit for drinking," he said.

At a hospital in the village of Gogjali on the eastern outskirts of Mosul, a medical source said civilians were starting to arrive with "cases of diarrhea and intestinal cramps, especially among children".

Iraqi commanders say around 40% of the eastern half of Mosul has been retaken in the offensive.

On Wednesday, Iraqi forces liberated one new neighbourhood amid heavy losses in ISIL's ranks, Ninawa Operations commander Nejim Edin Karim al-Jubury told Diyaruna.

Army and Counter-Terrorism Service forces "have fully liberated al-Ikhaa neighbourhood and are now advancing towards nearby Dorat al-Mahruq neighbourhood", he said.

"Advance is difficult due to the presence of civilians in their homes," he said. "However, we are achieving more and more success every day."