The bombing and shelling of the Eastern Ghouta district of Damascus is continuing to draw international outrage as images of injured and traumatised children are relayed through TV screens around the world.

Bishop Declan Lang, chair of the Catholic Bishops' Conference Department for International Affairs, has called the killing of civilians in Eastern Ghouta a 'grievous offence to our common humanity' and criticised the international community for failing to protect innocent people over seven years of war, conflict and turmoil in Syria.

'The slaughter of civilians, including many children, in Eastern Ghouta is a grievous offence to our common humanity,' he said.

'Their suffering underscores how over seven years of conflict in Syria, the international community has failed to protect the innocent.

'In this dark moment I urge Catholics in England and Wales to pray for the people of Eastern Ghouta and Syria; to encourage our own government to help end the violence; and to support generously those humanitarian agencies that are bravely working to save lives.'

Aid agencies including the Red Cross and the World Food programme have called for a ceasefire.

Britain's minister for the Middle East and North Africa, Alistair Burt, referred to the Assad regime's 'brutal siege' of the rebel-held enclave which with its 'escalating bombardment and reports of chemicals weapons use, is causing unprecedented levels of suffering'.

'The enclave has become a crucible of misery and violence, which is simply unacceptable in the 21st century,' he said.

He criticised the regime for refusing to allow medical evacuation and said: 'We call on the regime and its backers to cease this campaign of violence, to protect civilians and allow rapid and unhindered humanitarian access. As the international community has made clear to the Asad regime and its backers: the world is watching.'

Residents of the district have said they are waiting their 'turn to die' after rockets and barrel bombs fell in some of the most intense bombardments of the war. At least 10 people died in one village and more than 200 were injured early on Wednesday. At least 274 people have been killed in the district in the last three days, the British-based Syrian Observatory for Human Rights war monitor said.

Another 13 bodies, including five children, were recovered from the rubble of houses destroyed on Tuesday in the villages of Arbin and Saqba, the Observatory reported.

The densely populated agricultural district on the outskirts of Damascus is the last major area near the capital still under rebel control. The district, home to 400,000 people, has been besieged by government forces for years.

A massive escalation in air strikes since Sunday has become one of the most intense of the Syrian civil war, now entering its eighth year. The United Nations has denounced the bombardment, which has struck hospitals and other civilian infrastructure, saying such attacks could be war crimes.

The pace of the strikes appeared to slacken overnight, but its intensity resumed later on Wednesday morning, the Observatory said. Pro-government forces fired hundreds of rockets and dropped barrel bombs from helicopters on the district's towns and villages.

'We are waiting our turn to die. This is the only thing I can say,' said Bilal Abu Salah, 22, whose wife is five months pregnant with their first child in the biggest eastern Ghouta town, Douma.

They fear the terror of the bombardment will bring her into labour early, he said.

'Nearly all people living here live in shelters now. There are five or six families in one home. There is no food, no markets,' he said.

The UN children's fund UNICEF issued a blank 'statement' on Tuesday to express its outrage at mass casualties among Syrian children.

'No words will do justice to the children killed, their mothers, their fathers and their loved ones,' the release from UNICEF's regional director Geert Cappalaere began.

There followed 10 empty lines with quote marks indicating missing text, and an explanatory footnote.

'UNICEF is issuing this blank statement. We no longer have the words to describe children's suffering and our outrage,' it said.

'Do those inflicting the suffering still have words to justify their barbaric acts?'