Pope Benedict XVI is to visit Britain in 2010, the BBC has learned.
It will be the first papal visit to Britain since 1982, when Pope John Paul II's six-day tour drew huge crowds.
The news of Pope Benedict's visit comes after Gordon Brown extended a formal invitation to the Pope during a private audience in February.
A spokesman for the prime minister said he was "delighted" and "it would be a moving and momentous occasion for the whole country".
Details of his visit have yet to emerge but the trip is set to be the first official state visit by a pontiff - John Paul II's visit in May 1982 was on a pastoral basis and did not follow an official invitation by the UK government.
Masses were held in cities including Cardiff, London, Liverpool, Manchester and Edinburgh and he also met the Queen and Archbishop of Canterbury.
A spokesman for Prime Minister Gordon Brown said: "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."
Conservative leader David Cameron said he was "delighted" to hear of the possible visit.
He said: "Such a visit - the first in over a quarter of a century - would be greatly welcomed not only by Roman Catholics but by the country as a whole."
The Roman Catholic Church in England and Wales also sent the Pope a formal invitation in 2007.
The Archbishop of Canterbury, Dr Rowan Williams, said he had long hoped for such a visit.
He 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."
The BBC's Robert Piggott said Mr Brown, who comes from a staunchly Protestant background, has met Pope Benedict three times.
Our correspondent said the prime minister's invitation in February had been "warmly received" by the Vatican and was linked to the beatification of Cardinal Newman - England's most celebrated convert to Roman Catholicism.
Closer to sainthood
The Pope, who is 82, is said to have a particular interest in Newman and to support his canonisation, he said.
Earlier this year, Pope Benedict approved as a miracle the cure of a US Roman Catholic deacon from a crippling spinal disease, bringing Cardinal Newman, who died in 1890, one step closer to sainthood.
Deacon Jack Sullivan, who is to visit Britain in November, said he became completely free of pain after praying to Cardinal Newman in 2001.
It is not yet known when and where Pope Benedict will visit but our correspondent said it was likely to be another six-day trip.
He said there was a possibility that the Pope might visit Northern Ireland - unlike Pope John II who, on his visit to the Irish Republic in 1982, prayed for an end to sectarian violence in the North.
Pope Benedict's visit would only be the second by a head of the Catholic Church since Henry VIII declared himself head of the church in England more than 500 years ago.
There are an estimated 4.2 million Catholics in England and Wales.
The National Secular Society said it was planning demonstrations against the visit in protest at what it called Pope Benedict's "intransigence and fundamentalism".
A spokesman for the society said it would "make clear to the Pope that whatever celebrations the government lays on for him, he is not welcomed here by everyone".
I am delighted that we have invited the Holy Father to Britain. It is a measure of how far the UK has come in its respect for what is very likely the largest practising Christian Church in the country. The relationship has evoked historical misgivings and conflict over many years. However, genuine people of good will respect all our faith groups that strive to make ours a better community. I feel very proud.
Chris Burke, Lincoln
I now know when I'll be taking my holidays next year!
Brian Brown, London
It's good to see that the Pope is on a formal visit to visit England and Wales' many millions of Catholics. I'm not sure if I'll go and see him, but whilst, as your article points out, Gordon Brown is "staunchly Protestant", it is 500 years since The Reformation, so hopefully a little religious tolerance has crept into the country since then!
Sinead, St Albans
It is wonderful news, the atmosphere during John Paul II's visit in 1982 was amazing, everyone prayerful and united. It will bring a renewal to the already growing Catholic faith in the UK.
Stephen Tsang, London