UN laments living hell

Syrian regime forces advanced yesterday in Aleppo after Russia unleashed dozens of air strikes, as the UN's top aid official decried the "living hell" suffered by residents in the city's rebel-held east.

The devastating five-year war in Syria has ravaged second city Aleppo, once the country's economic hub but now torn apart by fighting between government troops and rebel forces.

The army of President Bashar al-Assad announced a major push on September 22 to capture Aleppo's opposition-held east and has gained ground in the city with the help of ally Moscow.

Dozens of air strikes pounded multiple battlefronts in the devastated city on Sunday, AFP's correspondent said.

The Syrian Observatory for Human Rights said Russian raids "helped regime forces to advance in the north of the city," where they reached the outskirts of the opposition-held Al-Heluk district.

If loyalist fighters seize Al-Heluk, Bustan al-Basha and Sakhur -- all rebel-controlled neighbourhoods in Aleppo's north -- they will confine opposition factions to a small section of the city's southeast.

Assad's Russian-backed military campaign in Aleppo has sparked international outrage after a series of air strikes on civilian infrastructure, including most recently on the largest hospital in the city's east.

Two barrel bombs hit the M10 hospital on Saturday, according to the Syrian American Medical Society (SAMS), which supports the facility.

United Nations aid chief Stephen O'Brien fiercely criticised the attack and yesterday called for immediate action to end the "living hell" of civilians in Aleppo's east.

O'Brien said the latest indiscriminate bombings subjected residents to "a level of savagery that no human should have to endure.

"The clock is ticking. Stop the carnage now," he added.

On Saturday, European Parliament president Martin Schulz called the hospital bombing a "war crime", tweeting that the international community "must unite to prevent (the) city's annihilation".

French Foreign Minister Jean-Marc Ayrault said "the systematic targeting of structures and health workers is particularly unjustifiable".

Syria's armed forces yesterday called on rebel fighters in east Aleppo to abandon their positions "and let civilians live their normal lives."

"The Russian and Syrian armies will secure safe passage and aid" to any opposition fighters that defect, said the statement, distributed on Syrian state news agency SANA.

Also yesterday, Russian strikes in the central Syrian province of Hama killed six members of a rebel group that has received US backing, according to the Observatory.