King Charles III will sit apart from the Royal family at the Easter Matins service in St George's Chapel at Windsor Castle on Sunday to protect his health.
The monarch and his wife Camilla will be seated away from other family members as he makes his first public appearance since beginning treatment for cancer almost two months ago, according to The Telegraph.
The arrangement has been agreed by Charles' medical team and comes as a positive sign of the progress of the King's recovery.
A source told the newspaper the seating plan would provide an 'acceptable' environment and level of risk for Charles to attend.
Royal aides also revealed earlier this week that the couple would be 'accompanied by other members of the Royal Family', although no further names were given.
The Prince and Princess of Wales and their children George, Charlotte and Louis will not be there as they spend the holidays together after Kate's cancer diagnosis.
King Charles III during the recording of the The King's audio message which was played at the Royal Maundy Service at Worcester Cathedral on Thursday
2023 - King Charles III and Queen Camilla with Princess Anne and Prince Andrew as they attend the Easter Mattins Service in St George's Chapel at Windsor Castle on April 9 last year
Charles and Camilla will go to the Easter Matins Service - as it is officially known - which will run for one hour from 10.45am until 11.45am, according to the chapel.
The service will be preceded by holy communion from 8.30am until 9am. There will also be a said eucharist from 12pm to 12.45pm, then evensong at 3.30pm to 4.15pm.
The King has been receiving treatment for an undisclosed form of cancer since early February after he had an operation for an enlarged prostate at the London Clinic.
It comes a week after Charles's daughter-in-law Kate revealed she had been diagnosed with cancer and was undergoing preventative chemotherapy.
William and Kate will not attend the service, which is unlikely to be a large family gathering or service because Charles has paused public-facing royal duties.
William is due to return to public duties after his children return to school following the Easter break.
For now, he will continue to balance supporting his wife and family, and maintaining his official duties as he has done since her operation in January.
2023 -- The Prince and Princess of Wales with George, Charlotte and Louis at the Easter Mattins Service at St George's Chapel on April 9, 2023
2022 -- Prince William and Kate with Prince George and Princess Charlotte attend the Easter Mattins Service at St George's Chapel at Windsor Castle on April 17, 2022
2019 -- Members of the Royal Family including Prince Harry, Kate and William watch as Queen Elizabeth II arrives for the Easter Mattins Service at St George's Chapel om April 21, 2019
It is not known how long Kate will be receiving treatment but it is understood she may be keen to attend events as and when she feels able to, in line with medical advice, although this will not indicate a return to full-time duties.
Charles's Easter Sunday engagement will be seen as the King making a move to reassure the public following the shock news.
The King is still undergoing treatment for cancer himself, but has been carrying out low-key official duties behind palace walls.
Although the Easter service is within the grounds of the castle, the King and Queen will be seen arriving, and are often watched by staff living at Windsor, who usually gather on a grassy bank nearby or watch from their doorsteps.
At last year's service, the King and Queen attended along with Princess Anne, Prince Andrew, Prince Edward, Sophie and Vice Admiral Sir Timothy Laurence.