A former Archbishop of Canterbury has attacked David Cameron for doing more than any other recent political leader to feed Christian anxieties that they are part of a persecuted minority.
Lord Carey said it was a "bit rich" to hear Mr Cameron tell religious leaders to face down aggressive secularisation when the coalition seemed to be "aiding and abetting" such a practice.
In an article for the Daily Mail he wrote: "I like David Cameron and believe he is genuinely sincere in his desire to make Britain a generous nation where we care for one another and where people of faith may exercise their beliefs fully.
"But it was a bit rich to hear that the Prime Minister has told religious leaders that they should 'stand up and oppose aggressive secularisation' when it seems that his Government is aiding and abetting this aggression every step of the way.
"At his pre-Easter Downing Street reception for faith leaders, he said that he supported Christians' right to practise their faith. Yet many Christians doubt his sincerity. According to a new ComRes poll more than two-thirds of Christians feel that they are part of a 'persecuted minority'. Their fears may be exaggerated because few in the UK are actually persecuted, but the Prime Minister has done more than any other recent political leader to feed these anxieties.
"He seems to have forgotten in spite of his oft-repeated support for the right of Christians to wear the cross, that lawyers acting for the coalition argued only months ago in the Strasbourg court that those sacked for wearing a cross against their employer's wishes should simply get another job."
Lord Carey said he was "very suspicious" that behind plans for gay marriage "there lurks an aggressive secularist and relativist approach towards an institution that has glued society". He added: "The danger I believe that the Government is courting with its approach both to marriage and religious freedom is the alienation of a large minority of people who only a few years ago would have been considered pillars of society."
A No 10 spokesman said: "This government strongly backs faith and Christianity in particular, including backing the rights of people wanting to wear crosses at work and hold prayers at council meetings, after a decade of secularism and political correctness from the Labour Party. Christianity plays a vital part in the Big Society, from the many brilliant church schools to the huge number of charitable causes based in churches across the country.
"The Prime Minister values the profound contribution that Christianity has made and continues to make to the country, which is why he strongly backs it."
Keith Porteous Wood, executive director of the National Secular Society, said: "David Cameron should ignore Lord Carey's theocratic and anti-democratic blustering. Nothing in the proposed same-sex marriage laws require Christians to conduct or partake in same-sex marriage, and Lord Carey has no right to insist that his discriminatory and intolerant views should prevail over those of the public and Parliament. And, rightly, they will not be allowed to."