King Charles was briefly hospitalized for observation after experiencing temporary side effects from his ongoing cancer treatment, Buckingham Palace has confirmed.

In a statement, the palace explained: “Following scheduled and ongoing medical treatment for cancer this morning, the King experienced temporary side effects that required a short period of observation in hospital.

“His Majesty’s afternoon engagements were therefore postponed.

“His Majesty has now returned to Clarence House and as a precautionary measure, acting on medical advice, tomorrow’s diary programme will also be rescheduled.

“His Majesty would like to send his apologies to all those who may be inconvenienced or disappointed as a result.”

The King has since left the hospital and is resting at home while following medical guidance.

King Charles was diagnosed with an undisclosed type of cancer in February 2024. Despite still undergoing weekly treatment, he resumed his public duties in April.

At the time, the palace revealed that doctors had discovered a “separate issue of concern” during a hospital procedure for prostate enlargement.