The King will attend the Easter Mattins Service at St George’s Chapel at Windsor Castle on Easter Sunday, Buckingham Palace has announced.
The Queen and other members of the Royal Family will also attend.
Today, the King took part in an audience at the palace with community faith leaders from across the UK.
The event was to celebrate those taking part in the Windsor Leadership Trust programme, which organisers say encourages and supports dialogue, harmony and understanding at a time of heightened international tension.
Last Thursday the monarch was photographed in a car being driven out of Buckingham Palace.
In February, the King was pictured attending church in Sandringham – but it had not been confirmed until now that he would attend the Easter service in Windsor.
It will be the King’s most significant public appearance and major royal engagement since his cancer diagnosis.
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Much like on Christmas Day, several members of the Royal Family gather together to celebrate Easter, and are photographed walking in to the service.
Prince William, the Princess of Wales and their children Prince George, Princess Charlotte and Prince Louis will not be present on this occasion.
The family are spending the Easter holidays together following Kate’s announcement she is being treated for cancer.
Kate revealed she is undergoing preventative chemotherapy in a video message to the nation on Friday.
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She said it had “taken time” to explain her diagnosis to her children George, Charlotte and Louis in a way that is “appropriate for them, and to reassure them that I am going to be OK”.
The King’s Easter Sunday engagement will be seen as the monarch making a move to reassure the public following the shock news.
The 75-year-old is undergoing treatment for cancer himself, but has been carrying out low-key official duties behind palace walls.
The latest palace announcement comes after the King’s nephew, Peter Phillips – the son of Princess Anne, the Princess Royal – said the monarch was “frustrated” about the speed of his recovery.
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He told Sky News Australia: “He is very pragmatic, he understands that there’s a period of time that he really needs to focus on himself.
“But at the same time he is always pushing his staff and everybody – his doctors and nurses – to be able to say ‘actually can I do this, can I do that?’
“I think the overriding message would be that he’s obviously very keen to get back to a form of normality and is probably frustrated that recovery is taking a little longer than probably he would want it to.”
The King has been receiving treatment for an undisclosed form of cancer since early February, which was discovered after he was treated for an enlarged prostate.
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