LONDON (AP) — King Charles III will take part in his official birthday celebrations in a little over two weeks, as the monarch eases his way back into public duties while continuing to undergo cancer treatment, Buckingham Palace confirmed on Thursday.

The news came amid reports that Prince William’s wife, Kate, will miss a public rehearsal for the event as she, too, receives treatment for cancer. It remains unclear whether the Princess of Wales will attend the main ceremony, known as Trooping the Colour, on June 15, Britain's Press Association reported.

Kate has revealed few details about her illness or treatment since announcing her cancer diagnosis on March 22.

Charles had been returning to public duties before Prime Minister Rishi Sunak last week called a snap election. That forced the king to postpone engagements that might divert attention from the campaign, raising questions about whether he would attend the birthday celebration.

Trooping the Colour is a 460-year old tradition in which troops in full dress uniform parade past the king with their ceremonial flag, also known as their “colour.”

Charles is likely to travel to the event by carriage with Queen Camilla and is expected to watch the Trooping ceremony seated on a dais, rather than on horseback as he did last year.