The King has returned to London for what is widely expected to be further treatment following his cancer diagnosis.
Charles and Queen Camilla flew by helicopter to Buckingham Palace from their private Sandringham home, and were driven the short distance to nearby Clarence House.
It was announced last week that the head of state has a “form of cancer” and at the weekend he issued a statement praising “all those organisations that support cancer patients”.
Charles has postponed all public-facing duties, but is continuing with behind-the-scenes work on his red boxes of state papers.
The Queen has been carrying out her royal diary of engagements and last week said her husband was doing “extremely well under the circumstances”.
She said the King, who underwent his first bout of cancer treatment last week, had been “very touched” by all the messages of support he received from the public.
On Sunday, he waved at cameras as he and Camilla walked to church – as they do every Sunday when they are in Norfolk – for the 11am service.
Buckingham Palace has not revealed what kind of cancer the King has, other than to rule out prostate cancer.
Whilst the King is being forced to step back from public duties, Camilla will continue with her own programme of royal engagements next week and her husband continues to work through his treatment plan.
She made a six-hour car journey from Sandringham on Thursday to attend an event at Salisbury Cathedral in Wiltshire after poor weather grounded her planned helicopter flight.
Her staff said she was determined not to let down the charities and military units she had come to support in Salisbury.
At the cathedral, Camilla told an air ambulance pilot that the King was “doing extremely well under the circumstances” and the messages of support were “very cheering”.
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