King charles queen camilla sandringham church 002 04 24

King Charlesis keeping up with official business.

The King, 75, who isundergoing treatment for cancer, was pictured in London on Wednesday morning waving to well-wishers as he was driven from his home, Clarence House.

The monarch is in London for private meetings and state business, including the audience he is due to hold with the U.K. Prime MinisterRishi Sunak, PEOPLE understands. He was pictured atthe regular meetingwith Mr. Sunak last week for the first time since revealing his cancer diagnosis.

King Charles and Rishi Sunak at Buckingham Palace on Feb. 21, 2024.JONATHAN BRADY/POOL/AFP via Getty

Britain’s King Charles III (R) speaks with Britain’s Prime Minister Rishi Sunak at Buckingham Palace, in central London, on February 21, 2024 for their first in-person audience since the King’s diagnosis with cancer.

JONATHAN BRADY/POOL/AFP via Getty

In the hours before that news was released, most members of the royal family had gathered, without King Charles, for aThanksgiving Service in Windsor Castlefor the late King Constantine of Greece on Tuesday. It underlined that while the King can carry out some meetings, he has curtailed most public-facing ones.

Also missing wasPrince William, whopulled out at the last minutedue to a personal matter, his office said. The Prince of Wales' wife,Kate Middleton, 42, who is recovering from herrecent abdominal surgery, also had to stay away although the palace shared that thePrincess of Wales “continues to be doing well.”

Queen Camillaformally led the royals at the service.

Although King Charles missed the memorial service for King Constantine, he was pictured on Wednesdaywearing a tribute to the late royal: a tie featuring Greek flags.

Queen Camilla at the Windsor service on Tuesday Feb. 27.CHRIS JACKSON/POOL/AFP via Getty Images

Princess Anne, Princess Royal, Britain’s Queen Camilla and Greece’s former Queen Anne-Marie leave after attending a thanksgiving service for the life of King Constantine of the Hellenes, at St George’s Chapel

CHRIS JACKSON/POOL/AFP via Getty Images

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On Tuesday, King Charlesled the sympathiesto Lady Gabriella, as a statement was issued on his behalf saying, “The King and The Queen have been informed of Thomas’s death and join Prince and Princess Michael of Kent and all those who knew him in grieving a much-loved member of the family. In particular, Their Majesties send their most heartfelt thoughts and prayers to Gabriella and to all the Kingston family.”

Thomas Kingston and Lady Gabriella in Sept. 2023.Dave Benett/Getty

Thomas Kingston and Lady Gabriella Windsor attend the private view for “Gabrielle Chanel. Fashion Manifesto” at the Victoria & Albert Museum on September 13, 2023

Dave Benett/Getty

King Charles was last seen inpictures released on Feb. 23celebrating some of the thousands of cards and letters he had received during his cancer treatment.

source: people.com