The Princess of Wales has said she is making “good progress” in her cancer treatment and announced she will join the royal family at Trooping the Colour.

Kate issued a candid statement outlining her personal cancer journey and said she is experiencing “good days and bad days” as she undergoes chemotherapy.

But she has begun to work from home, undertaking meetings with her foundation and Kensington Palace team, and hopes “to join a few public engagements over the summer” but stressed “I am not out of the woods yet”.

The princess has been receiving treatment for an undisclosed form of cancer since late February and her decision to choose a major national event on Saturday to return briefly to the public spotlight has been welcomed by the King.

A new photograph of the royal, taken earlier this week in the grounds of the Windsor Castle estate, shows Kate in a smart casual outfit stood in a tranquil setting against a weeping willow tree near a body of water.

She said in her statement: “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.”

The princess will be joined by her three children, Prince George, Princess Charlotte and Prince Louis, in a carriage for the traditional procession to Trooping the Colour and later they will gather with other royals on Buckingham Palace’s balcony for the fly-past.

Kate said: “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.”

The future Queen has received thousands of letters and cards from well-wishers, some sharing their own battles with cancer, and Kate said she had been “blown away” by the “kind messages” that had made a “world of difference to William and me and has helped us both through some of the harder times”.

A Buckingham Palace spokesperson 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”.