King Charles III is due to make his most significant public appearance since being diagnosed with cancer.
The King will join the Queen and other members of the Royal Family at an Easter Sunday service at St George's Chapel at Windsor Castle.
The Prince and Princess of Wales will not attend, as Catherine continues her cancer treatment.
The King has continued to work since the diagnosis, but all engagements so far have taken place in private.
Earlier this week the King spoke of his "great sadness" at missing the traditional Maundy Thursday service, which was instead attended by Queen Camilla.
His attendance at the Easter morning church service will be seen as an encouraging sign about his health.
The OceanNewsUK understands this does not mark the start of a return to public duties, but instead a careful first step back into the public eye.
Members of the public tend to gather near the chapel to catch a glimpse of the Royal Family ahead of the Easter Sunday service and it is thought the King will greet crowds from a distance, depending on the weather.
The King and Queen will sit away from other members of the congregation, but it is understood this is simply because they will sit in their traditional section of the chapel.
Last year marked the King's first Easter Sunday service as monarch, but the Royal Family have had to endure significant changes since then.
The King has not been at public events this year after having treatment for an enlarged prostate and later revealing that he had been diagnosed with a form of cancer.
Earlier this month, the Princess of Wales revealed in a video announcement that she is undergoing preventative treatment for cancer.
Catherine had abdominal surgery in January, when it was not known there was any cancer, but subsequent tests found it had been present.
There is no early return to official duties expected for the princess.
Neither the King's or Catherine's type of cancer has been revealed.
The diagnoses have depleted the ranks of working senior royals.
Queen Camilla has led the line for the royals for the past few months, increasingly carrying out trips on her own that would once have been the responsibility of her husband.
Prince William has kept up projects such as Earthshot and Homewards, but is likely to limit his travels to stay close to home and protect some kind of normal family life.
It is not known how future key dates in the royal calendar, such as Trooping the Colour in June, will be represented by members of the Royal Family, or when the King will return to public engagements.
