King Charles, 75, Announces Cancer Diagnosis, Postpones All Future Engagements for Now

People: After undergoing a procedure to treat an enlarged prostate last month, Buckingham Palace revealed on Monday that the King, 75, has cancer.

"During The King's recent hospital procedure for benign prostate enlargement, a separate issue of concern was noted. Subsequent diagnostic tests have identified a form of cancer," the palace said in a statement.

"His Majesty has today commenced a schedule of regular treatments, during which time he has been advised by doctors to postpone public-facing duties. Throughout this period, His Majesty will continue to undertake State business and official paperwork as usual," they continued.

"The King is grateful to his medical team for their swift intervention, which was made possible thanks to his recent hospital procedure. He remains wholly positive about his treatment and looks forward to returning to full public duty as soon as possible," the statement added. "His Majesty has chosen to share his diagnosis to prevent speculation and in the hope it may assist public understanding for all those around the world who are affected by cancer."

PEOPLE understands King Charles told his sons, Prince William and Prince Harry, about the diagnosis himself. A source says William, 41, is in regular contact with his father while Harry, 39, who relocated to California with his wife, Meghan Markle, in 2020, is expected to travel to the U.K. in the coming days

The King also personally informed his siblings, Princess Anne, Prince Andrew and Prince Edward, before the news was made public.

King Charles and Queen Camilla attend church on Feb. 4, 2024. (Max Mumby/Indigo/Getty)

King Charles was seen with Queen Camilla attending church on Sunday at St. Mary Magdalene Church near Sandringham, where the royal family traditionally attends mass on Christmas Day. It marked the monarch's first outing since leaving the hospital on Jan. 29 following a three-day stay after his prostate procedure.

King Charles returned to London from Sandringham on Monday to commence treatment as an out-patient.

The monarch had stepped away from public duties amid his recovery from prostate surgery, and it's not known when he will return to royal engagements given his cancer diagnosis. PEOPLE understands he will continue to receive red boxes, the monarch's daily delivery of documents needing his attention, and process state documents during his treatment.

There are currently no plans to appoint Counsellors of State to act on King Charles' behalf.

Last week, Queen Camilla, 76, visited Maggie’s Royal Free to officially open the new cancer support center at the Royal Free Hospital in London ahead of World Cancer Day. On Sunday, the royal family marked the day of recognition on social media by sharing photos of the Queen's outing.

Buckingham Palace revealed that the King was seeking treatment for an enlarged prostate on Jan. 17. “In common with thousands of men each year, The King has sought treatment for an enlarged prostate. His Majesty's condition is benign and he will attend hospital next week for a corrective procedure,” the palace statement said. “The King’s public engagements will be postponed for a short period of recuperation.”

He disclosed his diagnosis in hopes that it would inspire men to get checked. His decision proved to make an impact: after his announcement, there was a 1,000% increase in searches about prostate enlargement on the U.K.’s

Queen Camilla, King Charles, Prince William and Kate Middleton in Scotland on July 5, 2023. (YUI MOK/POOL/AFP via Getty)

It was announced earlier on Monday that Prince William will return to public duty this week. The Prince of Wales and heir to the throne, 41, cleared his schedule as his wife, Kate Middleton, had abdominal surgery on Jan. 16. After a 13-day hospital stay, the Princess of Wales, 42, is continuing her recovery at home in Windsor.