The Prime Minister will change his religion when he leaves office, it has been reported.
Tony Blair, an Anglican, regularly attends Roman Catholic Mass with his family.
Fr Michael Seed, a close family friend, hinted to The Times that he might convert.
There is confusion over whether a Roman Catholic can serve as Prime Minister.
The Catholic Emancipation Act of 1829 repealed many of the laws that had previously restricted the civil and human rights of Catholics, but also states that no Catholic adviser to the monarch may hold civil or military office.
Mrs Blair is a devout Roman Catholic, and the Blair’s two eldest sons attended an exclusive Church school.
There have been persistent rumours that Mr Blair will convert to Catholicism when he leaves office, fuelled by his attendance at Mass during his Christmas holiday in Maimi.
Alan Johnson, who had responsibility for overseeing the Sexual Orientation Regulations while he was Trade and Industry Secretary, is reported to have told MPs that an exemption for Roman Catholic adoption agencies was actively supported by the Prime Minister.
“They said Tony is the one who has been asking for this exemption,” a senior Labour MP told the paper.
The Prime Minister eventually decided not to grant an opt out after a cabinet row and a backbench revolt. Mr Blair is to resign as Prime Minister on 27th June.
Yesterday a Downing Street spokesman told the Daily Mail: “This story is always circulating in one form or another. The Prime Minister remains a member of the Church of England.”