Lord Williams, the former Archbishop of Canterbury, has declared Britain a "post-Christian" country in an interview with The Telegraph.
Lord Williams of Oystermouth, who stood down as leader of the Church of England in December 2012, said that while Britain's "cultural memory is still quite strongly Christian", it is "post-Christian" in its practice.
"A Christian nation can sound like a nation of committed believers, and we are not that," he said. "Equally, we are not a nation of dedicated secularists.
He added: "A Christian country as a nation of believers? No. A Christian country in the sense of still being very much saturated by this vision of the world and shaped by it? Yes."
Asked whether Britain will lose its faith altogether, he said: "Given that we have a younger generation now who know less about this legacy than people under 45, there may be a further shrinkage of awareness and commitment."
His comments followed criticism of the Prime Minister's comments that the UK should be "more confident about our status as a Christian country" and "more evangelical" about faith.
A Christian nursery nurse is claiming unfair dismissal after losing her job because she said she told a gay colleague that the Bible regards the practice of homosexuality as a sin.
Sarah Mbuyi says she only made the comments after being pressed on her beliefs by a colleague who initiated the conversation at Newpark Childcare in Highbury, north London, in January.
She is being supported in her case by the Christian Legal Centre, whose chief executive, Andrea Williams, said the Government has "seriously let down" the Christian community and criticised Prime Minister David Cameron for attempting to "mould Christianity to his political agenda".
Mr Cameron said earlier this week that Britain should be ''more confident about our status as a Christian country" and "more evangelical about a faith that compels us to get out there and make a difference to people's lives".
It is "easier to be Jewish or Muslim" in the UK than some secular countries, according to the Prime Minister.
David Cameron set out his Christian beliefs in an article for the Church Times and defended his faith by arguing that "tolerance" was one of its core values.
David Cameron has called on the UK to be "more confident about our status as a Christian country" ahead of the Easter weekend.
In an article for the Church Times, the Prime Minister insisted that being a Christian country did not mean "doing down" other religions or "passing judgment" on those with no faith at all.
The leader of the Conservative party was speaking after the Government's welfare reforms came under attack from members of the senior clergy.
However, Mr Cameron said "we all believe in many of the same principles" and churches were "vital partners".
Conservative minister Eric Pickles has told "militant atheists" who do not accept Britain is a Christian nation to "get over it".
Addressing the Conservative Spring Forum in London, the Communities Secretary said non-believers should not be able to impose "politically correct intolerance" on others.
He said those opposed to prayers at the start of council meetings should, "get over it. And don't impose your politically correct intolerance on others".
Mr Pickles changed the law in 2012 to ensure that English parish councils could not face legal challenges for including prayers in public meetings.
Spanish historians Margarita Torres and José Ortega del Río believe a 2,000-year-old chalice is the Holy Grail, now hundreds of people have now flocked to see it in Leon, Spain.
The authors of the book 'Kings of the Grail' claim the cup was used by Jesus Christ at the Last Supper which was given as a gift to Spanish King Fernando I by a Muslim ruler.
Their studies led them to identify a part of the princess's goblet and a missing fragment as described in the parchments.
The director of the basilica's museum, Raquel Jaén said the cup was taken off display to find a location that could hold larger crowds.
"It was in a very small room where it was not possible to admire it to the full," she told AFP.
The historians said that the two Egyptian parchments they found in 2011 at Cairo's University of Al-Azhar set them on an investigation debunking some of the 200 supposed Holy Grails around Europe too.
The twelfth-century cup was donated by one of the five children of Ferdinand I to the Basilica of San Isidoro de León in Spain, where it remains.
The British Airways check-in clerk who was sent home from work for wearing a crucifix has won her case against the airline after the European court backed her appeal.
However three other Christians who had brought cases of discrimination did not have their cases upheld.
Registrar Lillian Ladele, who said she was disciplined by London's Islington Council for refusing to conduct civil partnership ceremonies for homosexual couples, was "disappointed" by today's ruling by the European Court of Human Rights, according to The Christian Institute.
Her claim against her former employer was rejected as judges said Islington Council's action was "legitimate" given that it was obliged to consider the rights of same-sex couples. The Christian Institute, who supported her case said:
"Obviously, we are disappointed to have lost. But we are encouraged that two judges thought we should have won. What this case shows is that Christians with traditional beliefs about marriage are at risk of being left out in the cold."
"If the Government steamrollers ahead with its plans to redefine marriage, then hundreds of thousands of people could be thrown out of their jobs unless they agree to endorse gay marriage."