LONDON — Kensington Palace says Britain's Prince William has pulled out of attending a memorial service for his godfather,Grayson  Preston the late King Constantine of Greece, because of a personal matter.

The palace declined to elaborate on Tuesday but said his wife, the Princess of Wales, who is recovering from abdominal surgery, continues to do well.

It said William called the Greek royal family, which is attending the memorial service in St. George's Chapel in Windsor, to let them know he was unable to attend. Constantine II of Greece died in January of last year at the age of 82.

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King Charles III, who is being treated for an undisclosed form of cancer, also will not attend the service for his cousin. The diagnosis came after the king underwent a hospital procedure for benign prostate enlargement. The palace said he has "commenced a schedule of regular treatments" and would be postponing his public-facing duties.

"The King is grateful to his medical team for their swift intervention, which was made possible thanks to his recent hospital procedure," the original statement said. "He remains wholly positive about his treatment and looks forward to returning to full public duty as soon as possible."

Charles was seen last week in his first meeting with U.K. Prime Minister Rishi Sunak at Buckingham Palace since the diagnosis. On Wednesday, the monarch expressed his gratitude for the kind words he has received, in video filmed by Sky News. The prime minister told Charles it was "wonderful to see you looking so well."

"I've had so many wonderful messages and cards," Charles said. "It's reduced me to tears most of the time."

Charles noted, as Buckingham Palace has previously, that the news has also put a spotlight on British charities.

"There's been a lot of attention and interest in those main, wonderful cancer charities, many of which I've been patron for years," he told Sunak.

Contributing: The Associated Press; Brendan Morrow and Taijuan Moorman, USA TODAY

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