- By Daniela Relph, Royal Correspondent and Ali Abbas Ahmadi
- BBC News
A Kensington Palace spokesman said the Prince and Princess of Wales were “deeply touched by the kind messages” they received after Catherine was diagnosed with cancer.
Saturday's statement also added that they were “grateful” that the public understood their request for privacy.
Katherine revealed in a video message on Friday that she had begun treatment.
She received her diagnosis after tests performed after abdominal surgery showed “the presence of cancer.”
A Kensington Palace spokesman said: “The Prince and Princess have been hugely touched by the kind messages from people here in the UK, across the Commonwealth and around the world in response to Her Royal Highness’s letter.
“They have been extremely touched by the public’s warmth and support and are grateful that their request for privacy is understood at this time.”
This statement is the last we will hear from the Prince and Princess for a while.
It's both a thank you note and a polite warning – the couple saying the public aspect of this diagnosis is over and they want to be left alone.
It is also an acknowledgment of the overwhelmingly positive response to Katherine's video message.
Social media has been a toxic place for the princess in recent weeks due to wild rumors and gossip about her condition.
At the time of writing, Katherine's video message, posted on Instagram, had been liked nearly five million times.
Their final statement of thanks is the final chapter at this stage of the Princess's diagnosis, and Kensington Palace would like to put all speculation to rest.
The past few weeks have been difficult for the royal couple, their children and the team around them who have been trying to quell gossip and rumors – a task that has proven impossible.
The statement acknowledges the global interest in the princess's condition, with references to the UK, the Commonwealth and the world.
But the last few words are perhaps the most important – a direct plea for privacy as they try to escape the glare.
Prince George, Prince Charlotte and Prince Louis began their Easter school holidays on Friday.
They will not return to school until April 17, and we do not expect to see or hear from family during the break.
They have made it very clear that this is family time that they will fiercely protect.
The central element of any royal Easter is the church service on Easter Sunday, which is usually a powerful gathering of royals at St. George's Chapel in Windsor.
Prince William and Catherine have already said they will not attend Mass this year, but we may see the royal leading the family to church.
Buckingham Palace says they are “hopeful” he will be able to join the family next weekend.
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