A coalition of leading charities has called on the Government to open the door to vulnerable Syrians fleeing the bloodshed in their home country.
Organisations including Oxfam, Save the Children and Amnesty International criticised the British Government for keeping the UK's border under "lock and key".
The 25 charities signed a letter insisting that ministers needed to change their policy and accept Syrians in response to a call from the United Nations High Commissioner for Refugees (UNHCR) .
The letter says: "The UK deserves credit for its leadership in providing assistance to refugees in the region, including £600 million in aid, helping millions of families survive.
"However, given the scale and the gravity of the humanitarian crisis unfolding across the region, we would urge the UK to join the 18 other states participating in UNHCR's global resettlement programme. Those with family already in the UK should be allowed to reunite with their loved ones.
"People in neighbouring states have shown incredible compassion and opened their homes to hundreds of thousands of people but we all have a shared responsibility.
"It would be catastrophic if the neighbouring countries closed their borders to the thousands of people who flee the conflict every day. Yet how can we call on Syria's neighbours to keep their borders open to refugees if we keep our own under lock and key?"
The UNHCR has appealed to Western governments to accept 30,000 of the most vulnerable refugees trapped in the region.
So far 18 countries including Germany, France and the USA have signed up but the UNHCR is still over 10,000 places away from meeting its target.
The letter was organised by the Refugee Council, whose chief executive Maurice Wren said: "Given the scale and gravity of the crisis in Syria, we must do everything within our means to help people rebuild their lives in safety.
"For every vulnerable individual who is rescued from the region, resettlement would be life changing. Children would be able to go to school, women would be able to live without the constant fear of sexual violence, torture survivors could get the specialist help they need.
"Today we are appealing for the Government to show the same leadership on resettlement as they've shown in the relief effort to the region. Our message is clear: the UK must help the UNHCR reach its target for resettlement places.
"We cannot close the door to people who so urgently need our protection. Now is the time to act: people's lives could depend on it."
The Syrian government has proposed a ceasefire in war-torn Aleppo and a prisoner exchange with the opposition in a move which is being seen as an attempt to show president Bashar Assad is prepared to co-operate ahead of an international peace conference.
The offer was floated by Syrian Foreign Minister Walid al-Moallem during a visit to Moscow.
But it was met with scepticism by the opposition Syrian National Coalition, which has yet to decide whether to attend the peace talks in Montreux, Switzerland.
Shadow home secretary Yvette Cooper said it was "immoral" not to respond to the UNHCR call.
She said: "Western European countries are only being asked to help some hundreds of the most vulnerable refugees - and to help those who have family connections in Europe who can help and support them too.
"France, Germany, Austria, Finland, Holland, Ireland and others have all agreed to do their bit.
"People will feel ashamed that our government is one of the only ones to refuse to help. It is immoral to stand aside when countries as far afield as Canada and Australia are willing to help.
"The UK Government and charities supported by the British people have rightly provided significant aid to the region.
"But ministers need to rethink their blanket refusal to help those that need to leave the region even temporarily.
"Our country has responded to calls in the past and rightly has a reputation for helping those fleeing persecution built up over hundreds of years. We cannot and should not turn our backs on survivors of torture, and those at greatest risk."