THE Queen's Guards struck up a version of 'Congratulations' outside Buckingham Palace today.
World leaders joined in the welcome of the new royal baby as his arrival continued to spark a global tidal wave of interest.
The world's media remained camped outside St Mary's Hospital in London, hopeful of a sighting of the newborn, as the news continued to dominate the headlines.
After yesterday's announcement, the historic arrival was said to have been mentioned more than two million times on Twitter, while newspaper websites across the world brought the royal birth to the top of their home pages.
US president Barack Obama and wife Michelle sent their congratulations to the Duke and Duchess of Cambridge last night, saying: "We wish them all the happiness and blessings parenthood brings.
"The child enters the world at a time of promise and opportunity for our two nations. Given the special relationship between us, the American people are pleased to join with the people of the United Kingdom as they celebrate the birth of the young prince."
Australian prime minister Kevin Rudd wished the "royal bub" all the best on behalf of all Australians.
"This is a day of great joy," he said. "When a new bub comes into the world, any old day, any part of the world, it is frankly a time for rejoicing.
THE bells of Westminster Abbey sounded out today in celebration of the royal birth.Three of the bell ringers performing the task did the same for the new Prince's father more than 30 years ago.
When the Duke of Cambridge was born in June 1982, Clarke Walters helped ring a peal at the gothic church in central London in honour of the newest member of the royal family.
Mr Walters said it was "wonderful" to now be performing the peal for William's own baby son.
He also rang the celebratory bells for the Duke and Duchess of Cambridge's wedding at the Abbey two years ago.
A team of 10 from the Westminster Abbey Company of Ringers began ringing a full peal on the Abbey's 10 bells at 2pm to coincide with a gun salute in Green Park.
The Prince of Wales today said he was "thrilled and very excited" about the birth of his first grandchild.
And the Duchess of Cornwall described the arrival of the Prince of Cambridge as "a wonderfully uplifting moment for the country".
Charles and Camilla were met by cheering crowds of well-wishers on a visit to East Yorkshire.
Villager after villager offered the couple their congratulations as the royal couple walked around the green in Bugthorpe.
Charles said: "I'm thrilled and very excited."
The Duchess said Charles would make a "brilliant" grandfather.
"I think it's wonderful news. I think mother, son and father are all well," she told the BBC.
"And I think it's a wonderfully uplifting moment for the country.
"It's very exciting and it's wonderful for the grandfather - he's brilliant with children."
The village was decked out with Union flags and bunting for the visit.
One member of the crowd, local resident Robert Barrett, was one of the first to greet the Prince, saying "Morning Grandad", which raised a chuckle from Charles.
"He obviously likes being a grandad," Mr Barrett added.
A "quintessentially English" cocktail to be served in dainty tea cups is among a flurry of new recipes released in time to wet the royal baby's head.
PG Tips said its celebratory new take on the traditional cup of tea took inspiration from the Duke and Duchess of Cambridge's wedding day, with English ingredients resulting in a "rich and refreshing tipple packed full of Britishness".
The "royal tea cup" mixes strawberries, rose petals, PG Tips 'The Rich One' tea, optional gin and sparkling wine, cucumber, apple juice, elderflower and mint, and is described as perfect for a garden party, with afternoon tea or as an aperitif.
A PG Tips spokeswoman said: "We hope the Queen will be chuffed with this celebration cocktail and we'll definitely be enjoying a royal tea cup or two now the royal baby is born."
The arrival of the royal baby will be marked in tonight's episode of EastEnders after show bosses ordered some last-minute filming to reflect the birth.
A scene showing Dot Cotton (June Brown) and Abi Branning (Lorna Fitzgerald) discussing the happy news was filmed last night and will feature in the BBC soap tonight.
A spokeswoman for the show said: "This is such a momentous occasion for the Royal family, the country and of course the residents of Walford that we felt it should be marked in EastEnders history."
The Duke and Duchess of Cambridge spent last night with their son at St Mary's Hospital in London.
This is not the first time the show has celebrated historical events. It has previously made references to the couple's wedding and has honoured sporting achievements including Olympic success in 2012 and Andy Murray's Wimbledon win.
Torrential downpours and thunderstorms failed to deter royal well-wishers as scores of people braved the weather to queue outside Buckingham Palace well into the early hours.
A steady stream of hardy royal fans lined up against the Palace gates throughout the night to catch a brief glimpse of the ornate easel holding the framed A4 statement confirming the birth of the new Prince of Cambridge.
Those who decided against jostling for a spot at the gates at the height of the excitement last night returned early this morning, despite the onset of heavy showers which had thinned the joyous crowd shortly before midnight.
One police officer, approaching the end of an overnight shift at the gates, said this morning: "There were people here almost all night trying to get a look at the easel.
"The rain came at about 11pm and we saw nine-tenths of people go home.
"But some of them stayed until about 2am. Those who didn't fancy it last night started arriving at first light. It seems everybody wants to see it."
A dozen police officers formed a makeshift guard of honour at the gates in line with the easel in order to create two even queues snaking back to the Victoria Memorial outside the Palace this morning, as commuters sought to take a photograph of the easel on their way to work.
Hundreds of people waited under gloomy skies to see Charles and Camilla today.
They attended a celebratory service and listened to the choir sing in Bridlington Priory, in East Yorkshire, which was founded 900 years ago.
Musician Ben Couper played a violin piece he had composed and congratulated the prince afterwards.
Outside the priory, well-wishers cheered when the couple came out.
The prince met Charles Gardner, 70, his wife Janet, 66, and their son Matt, 39, from Cookridge, Leeds.
Mrs Gardner said: "I shook his hands and said 'congratulations'.
"He said 'I don't know if I have done a lot to deserve it. There's lots of proud grandmas and grandpas today'."
Mr Gardner senior shook the prince by both hands and said the experience was "absolutely marvellous".
Tourists watch the gun salute performed by the Honourable Artillery Company (HAC), from Gun Wharf at the Tower of London to mark the birth of the baby boy