The King will be named as the royal patron of the Queen Elizabeth Trust - a new charity commemorating the late Queen.
Queen Elizabeth II died aged 96 on 8 September 2022. Her 100th birthday would have taken place on Tuesday.
Set up as one of three projects honouring the Queen's legacy, the independent Queen Elizabeth Trust will offer grants for UK communities to develop and regenerate shared spaces.
It's set to be formally unveiled on Tuesday, along with the National Memorial landmark and gardens in St James's Park, and the Digital Memorial tribute to her life and service.
In support of the new charity, the government will make a one-off £40m endowment to start the projects. These could include developing underused buildings, green spaces and neighbourhood hubs in UK communities.
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Sir Damon Buffini, chair of the Queen Elizabeth Trust, said in a statement: "I'm honoured and excited to have been chosen as the founding Chair of the Queen Elizabeth Trust to help guide its direction from the start.
"This is a real chance to support communities across the United Kingdom and bring shared spaces back to life: places where people of all ages and backgrounds can meet, connect, and belong.
"As an organisation, we're ambitious about what we can achieve, and our goal is to significantly increase our impact by attracting support from others.
"I'm looking forward to rolling up my sleeves, listening and learning from communities, and seeing what we can make happen."
(c) Sky News 2026: King Charles to be royal patron of new charity in honour of Queen Elizabeth II
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