The King was seen smiling and waving at Sandringham estate in Norfolk where he is recovering from his first round of cancer treatment.
His Majesty was seen walking with Queen Camilla and waving to the public before being greeted by the Reverand Canon Paul Williams as he arrived at St Mary Magdalene Church this morning.
It is the first time he has been seen in public since his son Harry suggested in an interview with a US breakfast TV show that his father's illness could lead to a reconciliation between them.
Following King Charles's cancer diagnosis, Harry flew back to the UK to see him but they only spent around 45 minutes together.
READ MORE: King Charles leaves Sandringham Estate for cancer treatment
Harry and the King have been estranged since the younger duke stepped down as a working royal.
In the Good Morning America interview, Harry suggested a family illness could have a "re-unifying effect".
He also said "I love my family" and that he was "grateful" to be able to spend time with his father.
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