The plea, issued in an open letter signed by leading figures from the arts and business, calls on Britain to “step up and do more” to help “vulnerable refugees”.
It comes ahead of the UN High Commissioner for Refugees’ (UNHCR) meeting on Syrian refugees, which will be held in Geneva on Wednesday.
Campaigners hope the government will seize the “unique opportunity to do more by expanding the rules around family reunion”. The letter, backed by the Refugee Action and Citizens UK charities, recognises the “substantial aid” being used to help Syrian refugees, but says, “as the crisis grows, so too must our response”.
It says: “Many organisations and public figures have stepped up to help protect children in Calais, but, across Europe, thousands of refugee children are still stranded without hope or support. In the UK, Syrians with close family in refugee camps or conflict zones often cannot legally bring their relatives to safety.
“We are seeing the reality of this human crisis play out on our TV screens week after week. Families are desperate to reach their loved ones. Traumatised children have no-one to protect them.”
It ends: “We call on you to increase our resettlement commitment and to strengthen family reunion policies to help separated children and divided families.”
Law and Juliet Stevenson, who have both backed the letter, were among the famous faces who visited the Jungle camp, in Calais, last month to perform to refugees.
They also joined 145 stars in signing an open letter to Mr Cameron, asking him to help save children based at the makeshift camp, as sections of it were prepared for demolition by French authorities.