David Cameron praised the country's commitment to the Christian values of "giving, sharing and taking care ofothers" in his Christmas message.
"This Christmas I think we can be very proud as a country at how we honour these values through helping those in need at home and around the world," the Prime Minister said.
He particularly mentioned the sacrificial work of the British military and aid workers posted abroad, as well as those working in the public services and volunteering closer to home.
"So this Christmas, as we celebrate the birth of Christ with friends, families and neighbours, let us think about those in need at home and overseas, and of those extraordinary professionals and volunteers who help them," he said.
Cameron faced widespread criticism ealier this year for describing Britain as a Christian country.
Deputy Prime Minister Nick Clegg, who is an atheist, said the "core values" of Christmas – namely, love, charity and hope – are "universal, speaking to and uniting people of all faiths and none."
the video message, recorded at a primary school in West London, the Liberal Democrat leader referred to the Christmas truce on the Western Front in 1914.
"This Christmas and beyond, we can each do our bit to help secure the fairer, more peaceful world that the soldiers in 1914 longed for and our children deserve: reaching out to those people – wherever they may be – who feel isolated, who are caught up in conflict or who need our help," he said.
Labour Party leader Ed Miliband, who says he does not believe in God, also spoke of the Christmas truce in his seasonal greeting.
"In the midst of a tragic conflict the generosity, hope and sense of human solidarity that is characteristic of the Christian faith and culture came to the fore," Miliband said.
"We need the same sense of compassion in the face of the suffering and hatred that afflicts parts of our world. I am proud that the Labour movement has such deep roots in the Christian tradition of social activism and solidarity in the United Kingdom."
Earlier this week Miliband visited a homeless shelter for women in London, run by the Church Army, and last week he encouraged church leaders to continue supporting social justice initiatives.
Speaking at an event organised by Christians on the Left, he said: "Politics still needs ideas because it is ideas that start movements. Food banks would not have been organised by a political party. It required a movement."
