The first aid delivery to reach a besieged rebel area of Damascus in weeks had to be cut short because of government-led shelling while aid workers were still in the vicinity, the International Red Cross Committee (ICRC) has said.

A convoy of 46 trucks entered eastern Ghouta on Monday for the first time since an intense government assault on the area began two weeks ago. It carried enough food for approximately 27,500 of the area’s estimated 400,000 population, but the World Health Organisation (WHO) said that up to 70 per cent of the medical supplies on board had been offloaded – a common practice in Syria’s war.

While aid workers were still distributing the cargo in the town of Douma shelling from government-held neighbourhoods resumed, the IRCR confirmed on Tuesday, leading nine of the trucks to evacuate with supplies still on board.

Boris Johnson suggests the UK could strike Syria in response to Assad's attack on eastern Ghouta

The fresh strikes combined with the discovery of bodies in rubble from previous days upped Monday’s death toll to around 90 people, by local counts – the highest since a supposed UN ceasefire was brokered on 24 February.

The humanitarian situation appears to be worsening due to the lack of food and adequate medical help and significant internal displacement is starting to occur, local activists said.

Families who have spent the last two weeks hiding in basements near the front lines are starting to flee further inside the besieged zone to escape shelling and air strikes, sources on the ground and monitors confirmed.

Eastern Ghouta bombings: Syrian war in pictures Show all 14 1 /14 Eastern Ghouta bombings: Syrian war in pictures Eastern Ghouta bombings: Syrian war in pictures A Syrian woman and children run for cover amid the rubble of buildings. AFP/Getty Eastern Ghouta bombings: Syrian war in pictures Smoke rises from buildings following the attack on the village of Mesraba in the rebel-held besieged Eastern Ghouta region on the outskirts of the capital Damascu. AFP/Getty Eastern Ghouta bombings: Syrian war in pictures Injured children receive medical treatment. EPA Eastern Ghouta bombings: Syrian war in pictures A Syrian man carries a child injured. AFP/Getty Eastern Ghouta bombings: Syrian war in pictures An injured child receives treatment following bombings on several areas of eastern Ghouta. EPA Eastern Ghouta bombings: Syrian war in pictures A child reacts inside a hospital after relatives were injured in the bombing. EPA Eastern Ghouta bombings: Syrian war in pictures Syrian children cry at a make-shift hospital in Douma following air strikes on the Syrian village of Mesraba. AFP/Getty Eastern Ghouta bombings: Syrian war in pictures Syrian Civil Defense group extinguishing a store during airstrikes and shelling by Syrian government forces. AP Eastern Ghouta bombings: Syrian war in pictures A wounded 12-year-old Syrian boy, cries as he receives treatment at a make-shift hospital. AFP/Getty Eastern Ghouta bombings: Syrian war in pictures Syrians carry a wounded man. AFP/Getty Eastern Ghouta bombings: Syrian war in pictures An injured man covered with blood at a medical point. Reuters Eastern Ghouta bombings: Syrian war in pictures People sit a medical point in the besieged town of Douma, Eastern Ghouta. Reuters Eastern Ghouta bombings: Syrian war in pictures Syrian Civil Defense running to help survivors. AP Eastern Ghouta bombings: Syrian war in pictures Injured children receive medical treatment. EPA

Humanitarian corridors opened by Russia to allow civilians to flee the area remain empty, however, as residents fear shelling of the routes by both government and rebel forces.

On Tuesday the Russian defence ministry offered rebels safe passage out of eastern Ghouta with their families – but unlike in other sieges, such as east Aleppo, there is no nearby rebel stronghold to evacuate to.The Russian proposal did not specify where the rebels would go but in previous deals insurgents have been given safe passage to Idlib province in northwest Syria.

More than 700 people have been killed in the two-week-old assault, monitors say, despite pleas from the UN and humanitarian organisations for both sides to uphold the supposed 30-day-ceasefire.

Damascus and its allies in Moscow argue that the rebel fighters they are targeting are members of banned terrorist groups who are not protected by the truce.

The Syrian army has captured more than a third of the enclave over the last three days in an attempt to split it in two.

The UN hopes to be able to send another convoy on Thursday, Jens Laerke of the body’s Coordination of Humanitarian Affairs (Ocha) office told reporters.

Scenes of devastation in Syria after deadly shelling and airstrikes and eastern Ghouta

Meanwhile, medical staff in Hammouriya in eastern Ghouta reported 12 people from two families were admitted to hospital with chlorine gas inhalation symptoms after a strike late on Monday night. There were no fatalities.

US President Donald Trump and French President Emmanuel Macron repeated their opposition to chemical weapons usage as a “red line” in Syria’s seven-year-old war last week.