The Princess of Wales Kate Middleton has opened up about being diagnosed with cancer.

In a moving video message this evening, Kate Middleton said she is in the early stages of preventative chemotherapy.

The cancer was discovered in post-operative tests following her major abdominal surgery in London in January, she said.

In recent months, as rumours spread worldwide about her absence from the public eye, Kate, 42, said she needed time to come to terms with the news and tell her children before informing the world.

“It has taken us time to explain everything to George, Charlotte and Louis in a way that is appropriate for them, and to reassure them that I am going to be ok,” she said.

She added: “It has been an incredibly tough couple of months for our entire family, but I’ve had a fantastic medical team who have taken great care of me, for which I am so grateful.”

She said her husband, Prince William, has been a great source of comfort and reassurance.

“This of course came as a huge shock, and William and I have been doing everything we can to process and manage this privately for the sake of our young family.”

The announcement comes as King Charles also undergoes cancer treatment.

“We hope that you will understand that, as a family, we now need some time, space and privacy while I complete my treatment. My work has always brought me a deep sense of joy and I look forward to being back when I am able, but for now I must focus on making a full recovery,” Kate said.

“I am also thinking of all those whose lives have been affected by cancer. For everyone facing this disease, in whatever form, please do not lose faith or hope. You are not alone.”