Well-wishers sing 'Happy Birthday' as Queen Elizabeth II turns 90
Well-wishers sang "Happy Birthday" to a smiling Queen Elizabeth II as she turned 90 on Thursday, a milestone occasion the monarch marked by lighting the first of a thousand beacons across Britain and the Commonwealth.
The sovereign, who has been on the throne since 1952 and steered Britain through the decline of its empire, wore a lime green outfit and matching hat to accept presents and flowers from the crowd in Windsor, who spontaneously broke into song.
The queen's eldest son and heir Prince Charles, 67, said "Mummy" was held in "love and affection" across Britain and the wider Commonwealth, as she lit the first beacon outside Windsor Castle, near London.
The sovereign, who last year overtook her great-great-grandmother queen Victoria to become Britain's longest-serving monarch, will later host a family dinner with her 94-year-old husband Prince Philip to celebrate.
In a speech in parliament, Prime Minister David Cameron said Britain was "uniquely blessed" to have her, calling Queen Elizabeth a "rock of strength".
Opposition socialist Labour leader Jeremy Corbyn, a rare republican in public life, added that, whatever "different views" people have about the monarchy, most believe the queen "has overwhelming support".
While still active, the head of state has scaled back her duties in recent years as Charles and his 33-year-old eldest son Prince William take a more prominent role.
The royals remain popular but some question what will happen when the queen -- who is in good health, enjoying regular rides on her favourite pony and walking her corgi dogs -- reaches the end of her life.
- 'Mummy' tribute, birthday cake -
In an editorial, The Times newspaper praised her as "a symbol of continuity and the best embodiment we have of a complex national identity".
But it warned the monarchy "will not long retain its popularity" if Charles, who often writes to ministers petitioning about issues close to his heart like the environment, is seen to breach the constitutional convention of neutrality as king.
Beacons were set ablaze across Britain and the Commonwealth Queen Elizabeth symbolically heads, with Charles leading well-wishers in three cheers as she lit the first.
"Your Majesty, Mummy, I find it very hard to believe you've reached your 90th year and I suddenly realised the other day that I've known you since you were 22 years old," he said.
The Prince of Wales said the beacon represented "the love and affection in which you are held throughout this country and the Commonwealth".
He wished her "the most special and happiest of birthdays on this occasion. And long may you reign over us".
To mark the royal birthday, there were also military gun salutes at London's Hyde Park and the Tower of London and crowds gathered outside Buckingham Palace.
Later, parliament will be lit up in the red, white and blue of the British flag.
The queen was presented with a three-tiered orange drizzle cake baked by Nadiya Hussain, winner of television cookery show "The Great British Bake Off".
- Picture with great-grandchildren -
Royal officials released new pictures of the queen taken by US celebrity photographer Annie Leibovitz.
They were shot at Windsor Castle, where the monarch will on Friday host US President Barack Obama and First Lady Michelle Obama.
In one photograph, the queen is pictured with four of her dogs outside the castle.
In another, she is surrounded by some of her youngest descendants, including her great-granddaughter Mia Tindall clutching one of her handbags.
The royal family is currently in a strong position due in part to the perception of the queen as separate from politics.
When The Sun newspaper published a story last month claiming she supported Britain leaving the European Union in a June referendum, Buckingham Palace swiftly complained to the press watchdog.
The monarchy has not always been on as sure a footing as it seems to be now.
It went through what the queen described as an "annus horribilis" or horrible year in 1992 when Charles separated from his first wife Diana, while two of her other children also went through breakups and Windsor Castle was hit by a fire.
The monarchy's popularity plunged after Diana died in a Paris car crash in 1997 and the queen was accused of reacting coldly.
Advisors subsequently steered the royals towards a more modern image.
Some 68 percent of Britons think the monarchy is good for Britain, according to a YouGov survey last year.
© 2016 AFP