She will join her husband and children for the King’s Birthday Parade on Saturday, riding in a carriage with Prince George, Princess Charlotte and Prince Louis before appearing with the full working family on the Buckingham Palace balcony.
In a written message to the public published on Friday evening (UK time), the Princess said she was “looking forward” to the event. The King is said to be “delighted” to have her there.
A spokesman for the King said: “His Majesty is delighted that the Princess is able to attend tomorrow’s events, and is much looking forward to all elements of the day.”
It is the first public engagement the Princess has been well enough to attend this year, and comes nearly three months after she released a video announcing that tests following her abdominal surgery had revealed cancer.
Palace aides have stressed that her appearance at Trooping does not mean she is returning to her normal full schedule of work.
The Princess has begun working from home when she is able, being briefed on her early-years project and attending some meetings recently.
She hopes to undertake some public engagements over the northern summer, with the record of her work appearing in the Court Circular when she is able to do so.
In a statement published by Kensington Palace, the Princess said she had been “blown away” by the messages of support she had received, and thanked members of the public who had shared their own experiences.
“It really has made the world of difference to William and me and has helped us both through some of the harder times,” she said.
“I am making good progress, but as anyone going through chemotherapy will know, there are good days and bad days.
“On those bad days you feel weak, tired and you have to give in to your body resting. But on the good days, when you feel stronger, you want to make the most of feeling well.
“My treatment is ongoing and will be for a few more months.
“On the days I feel well enough, it is a joy to engage with school life, spend personal time on the things that give me energy and positivity, as well as starting to do a little work from home.”
She added: “I’m looking forward to attending The King’s Birthday Parade this weekend with my family and hope to join a few public engagements over the summer, but equally knowing I am not out of the woods yet.
“I am learning how to be patient, especially with uncertainty. Taking each day as it comes, listening to my body, and allowing myself to take this much-needed time to heal.”
She finished by saying: “Thank you so much for your continued understanding, and to all of you who have so bravely shared your stories with me.”
The statement was accompanied by a new image of the Princess, taken in Windsor by Matt Porteous, a professional photographer, this week.
The Princess wrote her message herself. The palace has emphasised her continued need for peace and privacy. She will not attend Garter Day or Royal Ascot next week.
The Princess had abdominal surgery in January, and has not taken part in a public engagement since the walk to Sandringham Church at Christmas.
In March, she released a video telling the world she was having treatment after the discovery of cancer. At the time of the update, on March 22, the palace said the Princess would return to official duties only when she was “cleared to do so by her medical team”.
“She may be keen to attend events as and when she feels able to, in line with medical advice,” added a source at the time. “Any initial public events will not necessarily signal a return to a regular public schedule.”
Asked about how Prince William was feeling, a Kensington Palace spokesman said: “The Prince is pleased to see the Princess starting to engage with the work and projects that are important to her.
“He will continue to focus his time on supporting his wife and children, while continuing to undertake his public duties.”
The Princess’s appearance on Saturday will mean she will join her three children for what is a highlight of the royal calendar.
The Prince of Wales will ride in the procession, with the three children and the Princess travelling by carriage to the Horse Guards Parade, where they will watch from the Major General’s Office.
The King and Queen will also travel by carriage this year, in a concession to the King’s own cancer treatment.
The full working royal family will unite at Buckingham Palace for the traditional flypast.
Last Saturday, the Princess missed the Trooping the Colour rehearsal, the Colonel’s Review, at which she was set to play a key role for the first time as Colonel of the Irish Guards.
Instead, she wrote a letter telling them: “Being your colonel remains an honour, and I am very sorry that I’m unable to take the salute at this year’s Colonel’s Review. Please pass on my apologies to the whole regiment, I do hope that I am able to represent you all once again very soon.”
