Highly unusual move: The Pope is the first to stand down in the last 600 years

In November 2011, Andrea Tornielli – a well-placed reporter from the Vatican Insider, a project run by La Stampa newspaper in Italy – said Pope Benedict found it agonising to walk even short distances due to 'arthrosis', thought to be an Italian term for osteoarthritis, in his knees, hips and ankles.



The condition forced him to pull out of a trip to Brazil in July.

Mr Tornielli said this was why the Pope began using a moving platform to address crowds during mass in St Peter’s Basilica.

There have also been reports that the Pope was struggling to read texts.

Dr Alan Silman, the medical director of Arthritis Research UK, said Pope Benedict most likely has osteoarthritis, which causes people to lose the cartilage at the end of their joints, making it difficult to move around without pain.

He said: 'It would be painful for him to kneel while he's praying and could be excruciating when he tries to get up again.'

Affection: Pope Benedict XVI embraces Cardinal Angelo Sodano, Dean of the College of Cardinals, after the pontiff announced his retirement

Saying his farewells: The Pontiff embraces Cardinal Angelo Sodano after the consistory

Startled: New York Cardinal Timothy Dolan, tipped as an long-shot for the papacy, was shocked by the decision

Joe Korner, a spokesman for Britain's Stroke Association, said having a mild stroke also could be a warning of a possible major stroke in the future.



'I would imagine the pope has been warned this could happen and that he should make some changes to his lifestyle,' Korner said, including reducing stress levels.



Benedict has previously stated that Popes who are unable to do their job because of ill health should step down.



His deterioration during the last few months has been particularly noticeable and, according to his brother, he has been considering stepping down for some time.

Georg Ratzinger, who still lives in the family's native Germany, said he had been having trouble walking and his age was weighing on him.

'At this age, my brother wants more rest,' he said adding that the doctor had warned him not to take any more transatlantic trips.

Despite Benedict being open with his family, he appears to have said little to cardinals and staff at the Vatican.





VIDEO Spokesman: Pope no longer able to 'cope' with challenges

Pope Benedict XVI is to stand down as leader of the Catholic church, it was announced today



Pope Benedict XVI meets members of the Order of the Knights of Malta after the Mass to mark the 900th anniversary of the Order in Vatican City on Saturday. He said his health is too weak to continue in office

Pope Benedict XVI (left) during a service in Saint Peter's Basilica to mark 900th anniversary of the Order in Vatican City

CONCLAVE AND SMOKES SIGNALS: HOW THE CATHOLIC CHURCH ELECTS A POPE



Roman Catholic cardinals seeking a successor to Pope Benedict XVI will hold a conclave to elect a new pontiff. Only cardinals are eligible to take part in the conclave, which will continue until a successor is chosen. The cardinals will meet in the Vatican's ornate Sistine Chapel and hold two voting rounds a day until they choose a new pope with a two-thirds majority. They were traditionally locked into the Chapel, best known for the frescoed ceiling and altar wall painted by Michelangelo, and not allowed out until they chose a new pontiff.

They had to sleep in makeshift cells and share minimal sanitary facilities. But new regulations issued by Pope John Paul II in 1996 allow them to live in a new hotel built on Vatican grounds behind St. Peter's Basilica and even take walks in the tiny state's peaceful gardens between their voting rounds. Another reform lets the cardinals opt for a simple majority vote if they have not succeeded in electing a pope after about two weeks of balloting.

Most modern conclaves have lasted only a few days. When the cardinals are in agreement, the chosen one will say 'Accepto,' a puff of white smoke, above, will emerge from the chimney, bells will toll and a cardinal will appear at the central window of St Peter's Basilica to declare 'Habemus papam' - 'We have a pope'.

The decision to resign is highly unusual as the vast majority of incumbents die in office. He is the first pope to resign in 600 years.



The Most Rev Vincent Nichols, Archbishop of Westminster and leader of Catholics in England and Wales called on 'people of faith' to pray for the 85-year-old pontiff, saying that his announcement had shown 'great courage.'

'Pope Benedict's announcement today has shocked and surprised everyone,' he said.

'Yet, on reflection, I am sure that many will recognise it to be a decision of great courage and characteristic clarity of mind and action.'

Cardinal Cormac Murphy-O'Connor, who retired as Archbishop of Westminster in 2009, said: 'My reaction was one of surprise and then gratitude for his service and leadership of the Church over the past seven years in troubled times.

'He has been a great teacher, thinking particularly of his visit to Britain and the example he gave of being a Good Shepherd and a good pastor.'

The Most Rev Peter Smith, Archbishop of Southwark, said he had been 'quite taken aback' by the announcement.

'My first thought when I heard the news that he was resigning, my instinct was that it is because of his health and his frailty and he feels it is an incredibly responsible task to be the chief shepherd of the Church on earth,' he said.

German Chancellor Angela Merkel said she had the 'very highest respect' for his decision to step down.

'As chancellor, I thank Benedict XVI for his work and wish him from the bottom of my heart all the best for the coming years,' she said.

Merkel, who is a Protestant, praised Benedict for his efforts to promote dialogue with other Christian denominations and religions. She said that he 'reached out his hand to Jews as well as Muslims.'

New York Cardinal Timothy Dolan, tipped as an long-shot for the pope's replacement, said he was as startled as the rest of the world.

He said he felt a special bond with the pope because he was the one that appointed him archbishop of New York.

Senior political figures also paid tribute.



Prime Minister David Cameron, who met the Pontiff in Archbishop's House, near Westminster Cathedral in London on his visit to Britain in 2010, said: 'He has worked tirelessly to strengthen Britain's relations with the Holy See.

'His visit to Britain in 2010 is remembered with great respect and affection. He will be missed as a spiritual leader to millions.'

VIDEO NY Cardinal Timothy Dolan reacts to Pope's resignation

Ailing: Benedict's deterioration during the last few months has been particularly noticeable and, according to his brother, he has been considering stepping down for some time Extra help: In 2011, Pope Benedict XVI starting using a mobile platform while leading services at St Peter's Basilica in the Vatican

POPE BENEDICT'S RESIGNATION STATEMENT IN FULL Dear Brothers,

I have convoked you to this Consistory, not only for the three canonizations, but also to communicate to you a decision of great importance for the life of the Church.

After having repeatedly examined my conscience before God, I have come to the certainty that my strengths, due to an advanced age, are no longer suited to an adequate exercise of the Petrine ministry.

I am well aware that this ministry, due to its essential spiritual nature, must be carried out not only with words and deeds, but no less with prayer and suffering.

However, in today’s world, subject to so many rapid changes and shaken by questions of deep relevance for the life of faith, in order to govern the bark of Saint Peter and proclaim the Gospel, both strength of mind and body are necessary, strength which in the last few months, has deteriorated in me to the extent that I have had to recognize my incapacity to adequately fulfill the ministry entrusted to me. For this reason, and well aware of the seriousness of this act, with full freedom I declare that I renounce the ministry of Bishop of Rome, Successor of Saint Peter, entrusted to me by the Cardinals on 19 April 2005, in such a way, that as from 28 February 2013, at 20:00 hours, the See of Rome, the See of Saint Peter, will be vacant and a Conclave to elect the new Supreme Pontiff will have to be convoked by those whose competence it is. Dear Brothers, I thank you most sincerely for all the love and work with which you have supported me in my ministry and I ask pardon for all my defects.

And now, let us entrust the Holy Church to the care of Our Supreme Pastor, Our Lord Jesus Christ, and implore his holy Mother Mary, so that she may assist the Cardinal Fathers with her maternal solicitude, in electing a new Supreme Pontiff.

With regard to myself, I wish to also devotedly serve the Holy Church of God in the future through a life dedicated to prayer.



Labour leader Ed Miliband said Pope Benedict had made a 'brave' decision.

'Many people will remember his historic visit to the UK in 2010 - which was a very special moment for many, especially Catholics, across the country,' he said.

'His decision to stand down is a brave one and we know he will not have reached it lightly.

'The choice of a successor is clearly an important one for the Catholic Church.

'Our thoughts are with those who must make such a critical decision on behalf of millions around the world.'

Cardinal Joseph Ratzinger became Pope Benedict XVI when he took office at the age of 78 in April 2005.

He succeeded Pope John Paul II, who continued serving right up until his death despite suffering a number of health problems including cancer, osteoporosis and Parkinson's disease.



He also survived two assassination attempts, one of which left him severely injured.

Pope Benedict XVI's papacy has not been without controversy.



Most significantly were the child abuse scandals that have hounded most of his time in office.

In 2010, he was forced to apologise to victims of abuse by Irish Roman Catholic clergy, saying he was 'truly sorry' for their decades of suffering.

He rebuked Irish bishops for 'grave errors of judgment' in their handling of the scandal and ordered an investigation into the Irish Church, but he did not admit any Vatican responsibility for a cover-up.

He ordered an official inquiry into the abuse, which led to the resignation of several bishops in Ireland.



Benedict also served in the Hitler Youth during World War Two. Although membership was compulsory at the time, the issue dogged him through the early years of his papacy.

Throughout his career, he has also been viewed as a deeply conservative man who had headed up the Church's modern-day Inquisition.

However, once he took office he gained a reputation as a charming and shy man who won over many of his critics.



He was only the second non-Italian Pope since 1522 and the oldest on election since the 18th century.

He said after he was elected to the Papacy that he had prayed not to get the post and was hoping for a peaceful old age.

As the powerful Cardinal Joseph Ratzinger, he was already well-known within the Catholic world before his election to the top job.

His image on elevation to the Papacy was one of an enforcer of Catholic orthodoxy and a cerebral disciplinarian who was unafraid to crack down on liberals and dissidents within the church.

While Prefect of the Congregation for the Doctrine of the Faith (CDF), he gained the nickname 'God's Rottweiler' for his pursuit of Catholic theologians and clergy seen to stray from orthodox teaching.

VIDEO The Pope's last public appearance before he resigned

Pope Benedict XVI waves to pilgrims while standing on the balcony of St Peter's Basilica, Vatican City after being elected in April 2005

His pronouncements before becoming Pope included labelling homosexuality a 'more or less strong tendency ordered toward an intrinsic moral evil' and saying rock music could be a 'vehicle of anti-religion'.

The Pope has also proved himself to be strongly against the ordination of women as priests, euthanasia, abortion and the use of artificial birth control.

Since his election as Pontiff his image has softened, leading him to be dubbed 'Benedict the Benign' in some quarters - but he has also attracted considerable controversy.

The Pope's 2009 visit to Africa was overshadowed by a row sparked by comments he made while flying to the continent in which he rejected condoms in the fight against Aids.

His decision in 2009 to lift the ex-communication on renegade English cleric Richard Williamson, who made comments suggesting only 200,000 to 300,000 Jews died in the Holocaust and none perished in gas chambers, also caused uproar.

All smiles: The Queen and Prince Philip exchange gifts with Benedict XVI in the Morning Drawing Room at the Palace of Holyroodhouse in Edinburgh during the Pope's visit to the UK visit in 2010

Triumphant: Pope Benedict XVI arrives to give a speech at Westminster Hall, London on the second day of his State Visit in September 2010 The Pope later issued a letter expressing his regret about the damage the affair caused to relations with the Jewish community, saying he had not known about Williamson's stance on the Holocaust when he took the decision to lift the ex-communication. One of his biggest setbacks also came on a visit to Germany in 2006 when he was caught in a firestorm of criticism from the Islamic world after giving a lecture at his old university of Regensburg. Quoting from an obscure Medieval text, he cited the words of a Byzantine emperor who characterised some of the teachings of the Prophet Mohammed, Islam's founder, as 'evil and inhuman' - remarks that touched off widespread anger across the Muslim world. The anger and violence sparked by his comments including attacks on seven churches in the West Bank and Gaza posed one of the biggest international crises involving the Vatican in decades. In Somalia, gunmen killed an Italian nun and her bodyguard at the entrance of a hospital where she worked, in an attack that some feared was linked to the outrage over the Pope's remarks. Warm welcome: The Archbishop of Canterbury, Rowan Williams, greets Pope Benedict XVI at Lambeth Palace in central London on September 17, 2010

Popular: Benedict XVI drives past crowds of pilgrims in his Popemobile in Longridge, Birmingham, during his UK visit in 2010

Throngs: Pope Benedict XVI delivering the 'Urbi et Orbi' Message and blessing to faithful from the central loggia of St Peter's basilica after the Easter Holy Mass at The Vatican in April 2012 He later apologised, saying he was 'deeply sorry' about the angry reaction to his remarks about Islam and holy war, saying the text he quoted did not reflect his personal opinion. But in September 2010, the Pope flew enjoyed a triumphant four-day state visit to Britain after which he declared that the UK had a thirst for Christianity. In a final attack on the atheists who tried to wreck the visit, Benedict XVI said that the country has become ‘a highly secularised environment’. His speech was the culmination of a tour aimed at re-evangelising a country he believes has slipped away from its Christian roots. The popularity of his visit confounded opponents who predicted thin congregations and empty parks. In December, he joined Twitter to spread his message to more of his 1.2billion followers through the internet.



Sense of fun: Pope Benedict XVI waves from the Popemobile wearing a Mexican sombrero as he arrives to give a Mass in Bicentennial Park near Silao, Mexico, on March 25, 2012

Keeping up with the times: The Pope joined Twitter in December to get his message across to more of his 1.2billion followers

The Pope was made Archbishop of Munich and Freising in 1977 after a career as a university professor.

He was born in the village of Marktl am Inn in Bavaria - he explained on a visit to Germany after his election 'my heart beats Bavarian'.

His formative years coincided with the lifespan of the Third Reich. His family opposed National Socialism but did not participate in public resistance to the Nazis.

He was forced against his will into Hitler Youth at the age of 14 and into the Wehrmacht at 16, serving in an anti-aircraft unit before deserting towards the end of the war.

He was once viewed as a progressive within the Catholic Church and played a key role in the reforming Vatican II, the meeting between 1963 and 1965 that introduced sweeping reforms to the church.

It is believed that his experience of Marxist unrest amongst students in the theology faculty in Tubingen, southern Germany, in 1968 where he was a professor contributed to his conservative outlook.

In private, the Pope is known to be an accomplished pianist and a lover of Mozart.

He is also a cat lover and, as Cardinal Ratzinger, was known to have looked after stray cats in Rome.