King Charles’s spokesperson expressed the monarch’s pride for his daughter-in-law Kate Middleton after she revealed her cancer diagnosis last night.

Buckingham Palace said the King is “so proud of Catherine for her courage in speaking as she did”.

The pair have “remained in the closest contact with his beloved daughter-in-law throughout the past weeks” after they spent time in hospital together, according to the spokesperson.

They added that Charles and his wife, Camilla, “will continue to offer their love and support to the whole family through this difficult time”.

In a video statement released on Friday, Princess of Wales announced she was diagnosed with cancer after a planned abdominal surgery in January.

She said she is now undergoing preventative chemotherapy.

The news comes a few weeks after the monarch revealed he was diagnosed with cancer earlier this year following a separate procedure for a benign prostate enlargement.

Charles is now going through a schedule of regular treatments.

The two royals were treated at the London Clinic at the same time earlier this year.

The Palace has not revealed what kind of cancer either of the senior royals has, and it is unlikely to do so.

Prince Harry and Meghan Markle extended their sympathies to Kate from across the pond, saying: “We wish health and healing for Kate and the family, and hope they are able to do so privately and in peace.”

Kate’s brother James Middleton also posted on Instagram about the news, sharing an old photo of the two of them alongside the caption: “Over the years, we have climbed many mountains together. As a family, we will climb this one with you, too.”