The 75-year-old monarch was pictured in the back of a car alongside Camilla, 76, as the pair were driven to Clarence House, the King’s official residence, on Tuesday morning.
PEOPLE understands that the King has returned to London for his ongoing cancer treatment appointments and meetings with palace staff.
The King’s return to London comes after he and Camilla attended a church service at St Mary Magdalene Church in Sandringham, Norfolk on Sunday. Charles waved at photographers as he made his way to the church alongside his wife.
It was his first public outing since he began his cancer treatment last week.
“I would like to express my most heartfelt thanks for the many messages of support and good wishes I have received in recent days,” the statement began. “As all those who have been affected by cancer will know, such kind thoughts are the greatest comfort and encouragement.”
“It is equally heartening to hear how sharing my own diagnosis has helped promote public understanding and shine a light on the work of all those organisations which support cancer patients and their families across the U.K. and wider world,” the statement continued. “My lifelong admiration for their tireless care and dedication is all the greater as a result of my own personal experience.”
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The palace announced that the King had been diagnosed with cancer on Feb 5. The announcement, which did not specify what form of cancer Charles has been diagnosed with, came a week after his surgery for an enlarged prostate.