Many have made dangerous journeys with small children and babies and Save the Children's chief executive said children were "the first victims" of the conflict in the country.
"There is no safe place left in Syria, with shelling and violence omnipresent. Food and medicines have become scarce and basic necessities unaffordable. Syria's health system has collapsed and deadly childhood diseases – like measles - which had previously been all but eradicated have now returned, threatening the lives of hundreds of thousands of children," Justin Forsyth said.
He said that the "generous donation" from Baron Cohen and Fisher would help "highlight the tragedy of the issue today."
"These are desperate times for Syrian families facing bombs, bullets and torture in Syria. The couple's donation will save many thousands of lives and protect some of the most vulnerable children," he added.
David Miliband, the former U.K. foreign secretary and current president and chief executive of the International Rescue Committee – a nongovernmental aid organization - said that as hope for the end of the conflict recedes, "it is all the more important to meet the most basic human needs."
"Sacha and Isla's donation is a great expression of humanity, and a challenge to do more for the most vulnerable. I hope it is an example to many others seeking practical ways of making a difference during the Christmas and New Year season," he said in a statement.
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