Syrian regime forces, backed by Russian military and Shia militias, advance towards Deir Ezzor's centre, under Daesh control for years.

Syrian forces gather on a road in Bir Qabaqib, west of Deir Ezzor, after taking control of the area from Daesh on September 4, 2017.
Syrian forces gather on a road in Bir Qabaqib, west of Deir Ezzor, after taking control of the area from Daesh on September 4, 2017. (AFP)

Syria's army battled Daesh on the edges of Deir Ezzor on Monday, seeking to break the siege of a government enclave and oust the militants from a key stronghold.

Daesh has already lost more than half of its nearby bastion of Raqqa to attacking US-backed forces, and the loss of Deir Ezzor city and the surrounding oil-rich province would leave it with only a handful of isolated outposts.

The Syrian regime and allied forces have come to within three kilometres (two miles) of a regime-held enclave besieged by Daesh in Deir Ezzor, regime-run television said on Monday.

Deir Ezzor province borders Iraq, where Daesh has also been expelled from former strongholds Mosul and Tal Afar.

The militants hold large parts of Deir Ezzor province, and more than half the provincial capital Deir Ezzor city.

Syrian regime troops backed by ally Russia have been advancing towards Deir Ezzor city on several fronts for weeks, and overnight they reached the Brigade 137 base on its western edge, a monitor said.

Two Russian soldiers have been killed by artillery fire from the Daesh in the province of Deir Ezzor, where the army is battling jihadists, Russia's defence ministry said on Monday.

One serviceman was killed instantly and a second died from his wounds in hospital, according to a ministry statement quoted by Russian news agencies. 

The Britain-based Syrian Observatory for Human Rights said Syrian regime troops outside and inside the base were battling to break the Daesh siege of the base.

"There have been multiple collapses of the Daesh line in western Deir Ezzor province, allowing the Syrian regime army to move quickly and arrive 10 km (6 miles) from the besieged forces," a military source said.

"The siege on the Syrian regime troops will be broken within hours," he added.

Civilians trapped

Daesh seized large parts of Deir Ezzor province, including its many oilfields, in mid-2014 as it rampaged across Syria and Iraq.

By early 2015 it had also seized parts of Deir Ezzor city and laid siege to the remaining parts of it under regime control.

The siege tightened further earlier this year, when Daesh advanced and cut the regime-held parts of the city in two, with a southern section by the key military airport now divided from a northern sector.

An estimated 100,000 people remain in regime-held parts of the city, which had a pre-war population of some 300,000.

The Observatory estimates more than 10,000 people may live in the parts of the city held by Daesh, although precise information is hard to come by.

The siege has created a humanitarian crisis in the city, with food and medical shortages and soaring prices.

The Syrian regime has brought supplies in by helicopter, and the United Nations has periodically airdropped humanitarian aid, but the situation remains difficult for those under siege.

Conditions are also reportedly dire for civilians trapped in Daesh-held parts of the city, with activists also reporting food and medical shortages as well as water and electricity cuts.

Capturing Deir Ezzor would be a key gain for Syrian regime, which has scored a series of military victories in recent months with Russian support.

Source: TRTWorld and agencies