The Archbishop of Canterbury, Dr Rowan Williams, and the Roman Catholic Archbishop of Westminster, Cardinal Cormac Murphy-O'Connor, have introduced a new think-tank report that challenges the ongoing secularist campaign to drive Christ out of Christmas.

The release of Doing God: A Future for Faith in the Public Square by new think-tank Theos coincides with the release of the Royal Mail's Christ-less Christmas stamp collection earlier this week.

The Church of England expressed its regret at the noticeable absence of a Christian theme in the stamps which feature instead Santa Claus, a reindeer, snowmen and a Christmas tree.

The Doing God report throws its criticism in particular at "the annual rash of winterval stories" that have appeared at Christmas time over the years as councils attempt to rename Christmas as part of a trend towards politically correct public symbolism that ends up as "insipid and uninspiring", The Times reported.

In their foreword, Archbishop Williams and Cardinal Cormac Murphy-O'Connor have argued that British society is experiencing a "moment of perplexity" as the debate widens over the place of religion in public life and debate.

"Issues of belief and faith, of how human beings experience the world, have rarely been so important in a society, or so badly misunderstood," they say.

The two church leaders also argue that faith needs to be "given space" to contribute and challenge in order for society to flourish.

"Many secularist commentators argue that the growing role of faith in society represents a dangerous development," they say.

"However, they fail to recognise that public atheism is itself an intolerant faith position. If we pay attention to what is actually happening in the United Kingdom and beyond, we will see that religiously inspired public engagement need not be sectarian, and can in fact be radically inclusive."

The report has already attracted scathing criticism from the National Secular Society. Vice-president, Terry Sanderson, described the report as "self-serving, self-deluding and a recommendation for the imposition of a new authoritarianism on an unwilling population".

"The British public does not want its life to be dictated by religious institutions, which it sees as nasty, small-minded and controlling," he said.

Report author Nick Spencer said, however: "We should not react with bewilderment when a public figure does 'do God'. We should be less scared of public figures citing religious texts in mainstream contexts. We should be more willing to treat other value systems as coherent, reasonable and even valuable rather than as primitive or grotesque mutations of the liberal humanism to which every sane person adheres."