Unverified reports say 15 to 20 people died of starvation in the Syrian city of Deir al-Zor last year, the United Nations said on Saturday, warning that 200,000 residents there face a severe food shortage and sharply deteriorating conditions.

Western parts of the city have been under siege by Daesh militants since last March, leaving inhabitants with no electricity for more than 10 months and a water supply for only three hours a week, the U.N. said in a report.

Deir al-Zor is the most populous of about 15 besieged areas in Syria, where about 450,000 people are trapped and cut off from aid by the government, Daesh and other insurgent groups involved in the country's civil war, the Daily Star reported.

Another besieged population, 42,000 people trapped in the town of Madaya, has received two convoys of aid supplies this month, but local aid workers have reported 32 deaths from starvation.

There have been no flights into the Deir Al-Zor airport except by helicopter since September and malnutrition is widespread, according to the United Nations.

"Severe cases of malnutrition are reported by health personnel particularly among children with unverified reports of 15 - 20 people dying from starvation in 2015 (of whom four were children)," it said.

"All schools are functioning in the city however absenteeism among children is common as children suffer from frequent fainting due to malnutrition," it added.

Daesh militants "interrogate and harass people leaving the city and confiscate their documents", while the Syrian government "requires those wishing to leave by land or air to obtain authorization", the report said.

Source: MENA