Pope Benedict XVI will come to Britain next year, making the first state visit by a pontiff. He is expected to meet the Queen, the Supreme Governor of the Church of England, and may stay at Buckingham Palace.

The historic event, probably in September, is likely to overshadow even the triumphant pastoral visit of Pope John Paul II in 1982. Unlike John Paul II, whose visit almost did not take place because of the Falklands conflict, the pontiff will meet the Prime Minister in a series of events over three days, which it is hoped will finally consign to the past Britain’s post-Reformation legacy of anti-Catholic prejudice.

Gordon Brown extended an invitation during an audience in February and preparations have been under way for some time. The draft itinerary is understood to include Birmingham, Oxford and Edinburgh. The Pope is not expected to visit Northern Ireland.

A central part of the visit is likely to be the beatification of Cardinal John Henry Newman, which could take place in Birmingham, where he founded his Oratory.

The visit will be a triumphant beginning for the new Archbishop of Westminster, Vincent Nichols, and could also provide a boost for David Cameron, the Conservative leader, if he is prime minister then. As a practising member of the Church of England attending an Anglo-Catholic parish in Kensington, Mr Cameron is expected to find a soulmate in the conservative-minded German Pope.

The visit follows repeated overtures from Downing Street and Catholic leaders in recent years. Tony Blair offered an invitation while Prime Minister and, in 2006, Cardinal Cormac Murphy-O’Connor, then Archbishop of Westminster, wrote to the Pope asking him to consider a visit.

Although there was no official confirmation from Downing Street or the Holy See last night, senior government figures are confident that there will be an announcement soon.An architect in the plans is understood to have been Britain’s Ambassador to the Holy See, Francis Campbell, a Catholic. Mr Campbell’s tenure in Rome comes to an end in October, soon after the projected visit. He has raised the profile of the job to the extent that for the first time his replacement is likely to become a political appointment. Figures being talked about as future ambassadors include two Tory MPs — the convert from Anglicanism Ann Widdecombe and the Ampleforth-educated Michael Ancram, QC.

A spokesman for Mr Brown said last night: “The PM is obviously delighted at the prospect of a visit from Pope Benedict XVI to Britain. It would be a moving and momentous occasion for the whole country and he would undoubtedly receive the warmest of welcomes.”

Archbishop Nichols said he was “encouraged and pleased” at the news, and the Archbishop of Canterbury, Dr Rowan Williams, who was yesterday visiting the Anglican Church in Japan, said: “I’m sure I speak on behalf of Anglicans throughout Britain, in assuring him that he would be received with great warmth and joy.”

But a spokesman for the National Secular Society said it would organise “a coalition of groups to make clear to the Pope that whatever celebrations the Government lays on for him, he is not welcomed here by everyone”.