Prince Charles Toasts the Queen at 'Big Jubilee Lunch' in Honor of His Mother's Record 70-Year Reign

June 5, 2022, UK: The Prince of Wales and the Duchess of Cornwall, as Patron of the Big Lunch, during the Big Jubilee Lunch with tables set up on the pitch at The Oval cricket ground, London, on day four of the Platinum Jubilee celebrations. Picture date: Sunday June 5, 2022. (Credit Image: © Stefan Rousseau/PA Wire via ZUMA Press)
June 5, 2022, UK: The Prince of Wales and the Duchess of Cornwall, as Patron of the Big Lunch, during the Big Jubilee Lunch with tables set up on the pitch at The Oval cricket ground, London, on day four of the Platinum Jubilee celebrations. Picture date: Sunday June 5, 2022. (Credit Image: © Stefan Rousseau/PA Wire via ZUMA Press)

Stefan Rousseau/PA Wire via ZUMA Press Camilla, Duchess of Cornwall and Prince Charles

Prince Charles is toasting Queen Elizabeth's record-breaking reign in the most British way possible: by raising a cup of tea!

The Prince of Wales, 73, and Camilla, Duchess of Cornwall, 74, joined thousands of royal revelers at London's Oval Cricket Ground on Sunday for a Big Jubilee Lunch in honor of his mother's 70-year rule.

Charles and Camilla also cut a special Big Jubilee cake and viewed a unique felt art piece created by Lucy Sparrow depicting a celebratory tea party of Platinum Jubilee Pudding, scotch eggs and fruit platters.

The Big Jubilee Lunch is a special 2022 version of the U.K.s annual Big Lunch initiative, which sees thousands of people come together each year over "a cuppa" and a bite to eat.

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June 5, 2022, UK: The Prince of Wales and the Duchess of Cornwall, as Patron of the Big Lunch, attend the Big Jubilee Lunch with tables set up on the pitch at The Oval cricket ground, London, on day four of the Platinum Jubilee celebrations. Picture date: Sunday June 5, 2022. (Credit Image: © Stefan Rousseau/PA Wire via ZUMA Press)
June 5, 2022, UK: The Prince of Wales and the Duchess of Cornwall, as Patron of the Big Lunch, attend the Big Jubilee Lunch with tables set up on the pitch at The Oval cricket ground, London, on day four of the Platinum Jubilee celebrations. Picture date: Sunday June 5, 2022. (Credit Image: © Stefan Rousseau/PA Wire via ZUMA Press)

Stefan Rousseau/PA Wire via ZUMA Press Camilla, Duchess of Cornwall and Prince Charles

More than 85,000 people across the U.K. have signed up to take part in this year's Jubilee event, with tea parties being held throughout the Commonwealth and beyond — from Canada to Brazil, New Zealand to Japan and South Africa to Switzerland.

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Together with an estimated 16,000 other street parties, it's expected that between 10-12 million Brits will take to the streets on Sunday to wave a Union Jack and raise a glass — generally containing something far stronger than Charles' tea.

"Between 10 to 12 million people is a modest estimate in terms of the scale of participation, and that's testament to the community spirit and appetite for connection we know is out there," Big Jubilee director Peter Stewart told Sky News ahead of the event.

Mandatory Credit: Photo by Jamie Lorriman/WPA Pool/Shutterstock (12973322aj) In celebration of Her Majesty The Queen's Platinum Jubilee, Prince Charles and Camilla Duchess of Cornwall, as Patron of the Big Lunch, attend a Big Jubilee Lunch at The Oval, Kennington, London. Prince Charles and Camilla Duchess of Cornwall raise a toast to Mer Majesty the Queen on the cricket pitch at the Oval, South London Big Jubilee Lunch at The Oval, Kennington, London, UK - 05 Jun 2022

Jamie Lorriman/WPA Pool/Shutterstock Camilla, Duchess of Cornwall and Prince Charles

"Holding your own event isn't hard — just knock on your neighbors' doors, grab some nibbles and hang the bunting!"

Sunday's event isn't the first Big Jubilee Lunch that Charles and Camilla have attended. On Thursday the royals made their soap opera debuts in a special edition of the long-running BBC drama Eastenders, where they joined the cast for tea and cake in a fictional area of London known as "Albert Square."

On Saturday night, Charles and Camilla joined the royal family for a star-studded "Party at the Palace" concert. The Prince of Wales delivered an emotional speech in honor of his mother the Queen.

Mandatory Credit: Photo by Jonathan Buckmaster/AP/Shutterstock (12972717ay) Britain's Prince Charles accompanied by Camilla, Duchess of Cornwall, speaks on the stage during the Platinum Jubilee concert taking place in London, on the third of four days of celebrations to mark the Platinum Jubilee. The events over a long holiday weekend in the U.K. are meant to celebrate Queen Elizabeth II's 70 years of service Platinum Jubilee, London, United Kingdom - 04 Jun 2022

Jonathan Buckmaster/AP/Shutterstock Prince Charles

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"Your Majesty, Mummy," he began. "The scale of this evening's celebration – and the outpouring of warmth and affection over this whole Jubilee weekend – is our way of saying thank you – thank you from your family, the country, the Commonwealth, in fact the whole world."

The four-day celebration will conclude on Sunday afternoon with the Platinum Jubilee Pageant, a procession through the streets of London that will showcase iconic moments from the Queen's reign as well as highlight how society has changed over the past 70 years.