Prince Philip has taken a typically irreverent view on his own retirement telling one man who said he was sorry he was standing down: "Well I can't stand up for much longer".
The Duke of Edinburgh made himself and a crowd of guests roar with laughter while with the Queen at an Order of Merit service at St James's Palace just an hour after announcing he will end his public royal duties at the age of 95.
Mathematician Sir Michael Atiyah was left in hysterics after stopping him to say: "I'm sorry to hear you're standing down", to which the Duke replied: "Well I can't stand up much longer".
His well-earned retirement comes after 70 years dedicated service to Britain and Her Majesty, who has given him her "full support" to step down, the Daily Mail reports.
It was announced at a top secret emergency meeting called by Buckingham Palace and attended by other royals including his daughter Princess Anne.
The difficult decision was made by Philip himself and he will step back just before he and the Queen reach their 70th wedding anniversary in November. The Queen will continue her public engagements as she has always vowed to serve her country for as long as she lives.
Buckingham Palace said: "The Duke of Edinburgh has decided that he will no longer carry out public engagements from the autumn of this year. In taking this decision, the Duke has the full support of the Queen.
"The Duke of Edinburgh is patron, president or a member of over 780 organisations, with which he will continue to be associated, although he will no longer play an active role by attending engagements."
Last night the Mail revealed staff from the royal household across Britain were called to London today, which caused fevered speculation around the world about the health of the Queen and her husband.
However, Philip - Britain's longest-serving consort in history - is "fine" but has decided to end his formal royal duties having supported his wife in public on thousands of occasions since 1947.
In typical style the Duke and the Queen were back at work an hour after the announcement, attending an Order of Merit service at St James's Palace.
The Duke's retirement marks the end of an extraordinary lifetime's service to the country.
He has carried out more than 22,000 solo engagements in his long career and given more than 5000 speeches - but there are also the many thousands of other duties he has carried out behind the scenes since 1947.
Even at the age of 95, Philip has put the younger generation of royals to shame and undertook 219 official engagements in the UK last year, which was more than Prince William, the Duchess of Cambridge and Prince Harry put together.
The Queen and Philip called a halt to long-haul travel in recent years, handing this responsibility to the younger members of their family.
Philip is expected to spend more time at Windsor Castle, where he is ranger of Windsor Great Park and has overseen major developments at the estate. Although he is not involved in its day-to-day running, he still takes a keen interest.
And despite withdrawing from public contact with his charities and organisations, the Duke will still keep in touch via correspondence - like signing certificates and sending messages.
Although the Duke will continue to accompany his wife to some events, his children and grandchildren, especially William and Harry, are expected to take up some of his responsibilities.
Other members of "Team Windsor" like Princess Anne are expected to step in for their father.
The Duke of Cambridge has already announced he will be leaving his job as an air ambulance helicopter pilot in summer with the intention of taking on more royal duties.
Prime Minister Theresa May has led tributes to the Duke of Edinburgh after the announcement that he is standing aside from royal duties, saying the whole country would want to offer him "our deepest gratitude and good wishes".
May said Prince Philip had given "steadfast support" to the Queen and served the country in a way which would be "of huge benefit to us all for years to come".
She said: "On behalf of the whole country, I want to offer our deepest gratitude and good wishes to His Royal Highness the Duke of Edinburgh following today's announcement that he will stand down from public duties in the autumn.
"From his steadfast support for Her Majesty the Queen to his inspirational Duke of Edinburgh Awards and his patronage of hundreds of charities and good causes, his contribution to our United Kingdom, the Commonwealth and the wider world will be of huge benefit to us all for years to come."
Former Prime Minister David Cameron said: "HRH the Duke of Edinburgh is an outstanding public servant. We owe him a huge debt of gratitude. I always enjoyed his company, especially his BBQs!"
This is a reference to Philip's love of outdoor cooking, especially at Balmoral.
Labour leader Jeremy Corbyn also had words of praise for the Duke, saying his "clear sense of public duty" had inspired people for more than 60 years.
Corbyn said: "I would like to pay tribute to Prince Philip following his decision to retire from public service.
"He has dedicated his life to supporting the Queen and our country with a clear sense of public duty.
"His Duke of Edinburgh's Award scheme has inspired young people for more than 60 years in over 140 nations. We thank Prince Philip for his service to the country and wish him all the best in his well-earned retirement."
Scotland's First Minister Nicola Sturgeon said: "HRH the Duke of Edinburgh has dedicated his life to public service and the steadfast support he has given to the Queen throughout her reign is hugely admirable.
"His charity work, in particular his role as chairman of the Duke of Edinburgh Awards, has benefited millions of young people across Scotland. He also gave over 50 years of service to Edinburgh University during his time as Chancellor there.
"He has always served with enthusiasm and a healthy sense of humour. I have always thoroughly enjoyed any time that I have spent in his company.
"I know that, even as he steps back from public life, the Duke will continue to be a huge support to the Queen. I wish him all the very best for a happy and peaceful retirement."
The Mail revealed last night that Her Majesty's most senior aides called her entire household from across Britain to London for a 10am summit ahead of a royal announcement.
But royal sources said that internet rumours about the Queen's or the Duke of Edinburgh's health faltering were "wide of the mark" and the couple were "fine".
As speculation swirled yesterday the spokesman refused to say what the meeting is about but added: "There's no cause for alarm" and the Royal Standard remained at full mast over Buckingham Palace, meaning there has been no death in the royal family.
The Queen met Theresa May in London yesterday to dissolve Parliament for the General Election and Prince Philip opened a new stand at Lords cricket ground. Both looked in rude health and had later engagements in the capital.
Servants from royal residences across the country were ordered to London and addressed by the Lord Chamberlain, the most senior officer of the Royal Household, as well as Her Majesty's right-hand man, Private Secretary Sir Christopher Geidt.
Even her longest-serving staff were left in the dark about why the meeting was being called but multiple sources said it was "highly unusual".
"Everyone is on tenterhooks," said one source last night.
"Although meetings involving the entire royal household are occasionally called, the way this has been done at the 11th hour is highly unusual and suggests that there is something major to be disseminated.
"But at the moment, only those closest to her genuinely know what on Earth this is all about."
The Queen had just returned to her London residence following her extended Easter break at Windsor.
She turned 91 last month and her husband, Prince Philip, will celebrate his 96th birthday in June.
In recent years the Queen has, slowly but surely, been handing over a number of her more onerous duties, including all those involving long-haul travel, and many of her regular investitures.
Last year Buckingham Palace also announced that she would step down as patron of about 25 national organisations - including the NSPCC and Wimbledon tennis - after she turned 90 in April and in favour of younger members of her family.
Many have expressed concern, however, that she still conducts well over 300 engagements every year.
The Duke also helped the Queen through the deaths of her mother and sister in the Golden Jubilee year of 2002.
He has enjoyed good health throughout much of his life - recovering from a blocked coronary artery in 2011 and a bladder infection in 2012 - the latter leading him to miss most of the Queen's Diamond Jubilee celebrations.
He continued to take part in fast-paced, dangerous carriage-driving events, competing at international level until the age of 85.
When he turned 90 in June 2011 he insisted on no fuss, but the Queen bestowed on him a new title - Lord High Admiral, titular head of the Royal Navy.
It was a touching tribute to the man who gave up his military career to support his wife, and devote himself to royal service.
A symbol of continuity within the monarchy and public life, the Duke of Edinburgh is the person the Queen relies upon above all others.
Philip's first Private Secretary Michael Parker, a friend from the Navy, once revealed: "He told me the first day he offered me my job that his job, first, second and last was never to let her down."
Recently the Duke and Duchess of Cambridge announced they would be finally moving back to London from Norfolk, where Prince William works as an air ambulance pilot, to help shoulder the burden more.
Similarly, Prince Philip has been curtailing his commitments, having stepped down from a number of patronages when he turned 90.
There was also grave concern for the Queen and Philip's health over Christmas when both developed heavy colds, forcing the monarch to miss Christmas Day service for the first time in living memory.
It is unlikely, however, that any meeting would involve news of an abdication as the Queen has always vowed to serve her country for as long as she lives.
The Duke of Edinburgh was out and about yesterday as he joked about his prowess at unveiling plaques when he opened a new £25 million ($47m) stand at Lord's cricket ground in London.
Philip, famed for his off-the-cuff comments, quipped just before he pulled a cord to part a small curtain: "You're about to see the world's most experienced plaque-unveiler."
His comment was reminiscent of a joke made by his grandson, Prince Harry, who said of the Royal Family during a tree-planting ceremony: "It's what we do."
And when the Duke was shown a selection of cricket bats through the ages, from an 1890s blade used by Albert Trott to a huge example now ruled illegal, he looked at a baseball-style bat with a very long handle and said to former England captain Mike Gatting: "It's an offensive weapon."
Meanwhile the Duchess of Cambridge gave a baby lamb called Stinky a bottle of milk during a visit to the Farms for City Children in Arlingham, Gloucestershire - a charity set up by children's author Michael Morpurgo to teach inner-city children about farming.
The Duchess, wearing dark brown knee-length zip-up boots, light brown trousers and an outdoor jacket, had arrived at the farm for a private lunch with the children and staff. She then joined a story-time session led by Morpurgo, who founded the charity with his wife Clare in 1976.
The Duchess was then taken on a tour of the farm where she helped children - from Vauxhall in London - pot vegetable plants and plant onions in the allotments, as well as tending to the chicken coop.
Also yesterday, Kensington Palace said Prince Harry is to visit Singapore to stage a polo match in aid of his charity Sentebale and will also travel to Australia.
Harry will host the Singapore polo match in June in aid of his organisation based in Lesotho which provides support to African children living with HIV and Aids.
On Saturday, Harry was at Twickenham Stadium in South West London for the Army v Royal Navy annual rugby match.
Royal watchers are hoping to see Harry accompanied by his actress girlfriend Meghan Markle at the wedding of the Duchess of Cambridge's sister Pippa Middleton in Berkshire on May 20.
Other royal news yesterday concerned the centenary of the House of Windsor, which was commemorated with a new coin.
The Royal Family's name was radically switched 100 years ago in 1917 because of anti-German feeling during World War I.
Announcement a "canary in the mine"
Australia's top British Royalty expert, Associate Professor Giselle Bastin, says she suspects the announcement about Prince Philip is a precursor to the Queen stepping back from her duties as well.
The younger royals have already taken over much of the work, she pointed out.
"I kind of suspect this downgrading of his duties is a way of getting us used to the idea she's about to do the same. They often send a canary down the mine, usually a slightly lesser [royal] to try out the new thing and test the public's reaction a bit."
She thinks the public will barely notice the Queen stepping out of the limelight. "She'll just scale it back to the point where people won't notice she's not doing much at all. They will still keep their ceremonial duties, appearing on the balcony and waving every now and then. But they want the focus to go onto Charles a bit more - it's his to inherit so it makes sense to give him more screen time."
Philip stepping down is "absolutely understandably given the man's age - how many people are working at all at 95"?
"He's followed causes he's pretty passionate about - the World Wildlife Fund, housing developments; he hasn't shirked his duties at all. Not always perhaps as graciously as he might have but he has kept his side of the bargain."
"He just must be very tired. He can still keep abreast of things without going out shaking hands and unveiling plaques like he has done for 60-odd years."
She was doubtful that anyone had died yesterday. If Queen Elizabeth dies the code phrase is "London Bridge is down" (although now that has been widely publicised it has probably been changed, she said). Prince Philip's code phrase will be "Forth Bridge is down" but she suspected Forth Bridge was very much still standing.
"Something was not making sense, especially that they were recalling the household. If it was a significant death they wouldn't recall the household - they would just bunker down, there would be a media blackout with nothing said.
"It's almost as if someone got the wrong end of the stick and went crazy with it. I wouldn't really believe anything had happened till members of the family turned up at Buckingham Palace - because like most families, they want all the family members to be informed before the word gets out. It seemed very odd. And specially as he was seen yesterday looking robust for his age. She was too."
She thought the announcement might have been about the snap election being called - it would have interrupted the Queen's annual week at Ascot which the monarch would have been upset about.
"Nonetheless it was an interesting exercise, because it gave us a glimpse into what is going to be really inevitable quite soon."
She believes the royals "absolutely love" the furious speculation that happened yesterday. "It shows how much they do matter - they love that affirmation because they're there to be seen. If everyone went 'Whatever, let's get back to watching the Great British Bakeoff' that would give them cause for concern."
- Additional reporting NZ Herald