Prince William joins King Charles for rare joint outing as he makes major announcement

King Charles has stepped out for a rare joint appearance with Prince William as he made a major announcement.

Father and son attended a reception at the Natural History Museum in London to mark six weeks to go until world leaders gather in Belém, Brazil, for theCOP30 climate change summit.And at the event tonight, it was revealed that William will be attending the summit next month on behalf of his father. William is already travelling to Brazil for the Earthshot Prize Awards ceremony taking place in Rio de Janeiro on November 5. While there, the prince will undertake a number of engagements relating to the environment before travelling to Belém to attend the crucial summit.

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At COP30, William will give a speech, with the announcement seen as a major development of the heir to the throne’s responsibilities on the world stage.

The King, 76, who is still being treated for cancer, previously led at the event in person on the royal front. It will be the first time William has travelled internationally for a COP summit, having previously attended COP26 in Glasgow in 2021, as did Charles.

Tonight's event in London, hosted by the Natural History Museum's Dr Doug Gurr and Deputy Prime Minister David Lammy, saw Charles and William meet changemakers, who are taking action against climate change both in the UK and internationally.

They included representatives from finance, business, science and education as well the former Prime Minister Theresa May. They learned about some of the innovative solutions to climate change that have been developed in the UK.

Dr Doug Gurr said: "We need everyone in society to get on board to tackle the twin challenges of biodiversity loss and climate change.

"The collective commitment to act for the planet was palpable tonight - from the support of His Majesty the King and His Royal Highness the Prince of Wales and the leadership of the UK Government, to the school students who are striving to transform their school grounds, making them a haven for wildlife."

In 2022, the King missed the COP27 summit in Egypt, the first climate change summit of his reign, following advice from the Government while Liz Truss was prime minister, despite it being widely reported he had hoped to attend in person.

Charles, who also attended in 2015 and 2021, went on to fly to Dubai for Cop28 in 2023, where he gave the opening address to world leaders. He warned delegates that the world remains “dreadfully far off track” in key climate targets and called for meaningful change. But he missed COP29 in Azerbaijan in 2024 after being diagnosed with cancer earlier that year.

Both the King and the Prince of Wales have been vocal on tackling climate change and the event comes after it was confirmed Charles's lifelong battle to bring nature and humanity into harmony is to be chronicled in a new Amazon Prime documentary.

The King said it is his “fondest hope” that it will encourage a new audience to embrace his environmental philosophy and warned it has never been more important for the world to focus its efforts on protecting the planet.

The documentary, which has the working title Finding Harmony: A King’s Vision, will feature Charles’ own reflections on his lifelong commitment to promoting a sustainable world and is being billed as an uplifting tale of the power of “hope and resilience”.

Produced by Passion Planet in collaboration with the monarch’s charity The King’s Foundation for Amazon MGM Studios, it will launch exclusively on Prime Video in more than 240 countries and territories worldwide early next year.

The King said: "This film will, I hope, demonstrate just some of the remarkable work being done around the world to put Harmony into practice, from the forests of Guyana to sustainable communities in India – and, closer to home, through the work of my King’s Foundation at Dumfries House and Highgrove.

"Never has it been more important for the world to make a concerted effort to protect and prioritise our planet, and to restore our relationship with it."