Kate Middleton
Catherine, Duchess of Cambridge and Prince William, Duke of Cambridge attend the traditional Easter Sunday church service at St George's Chapel, Windsor Castle on April 21, 2019 in Windsor, England. Getty Images/Max Mumby

Prince William warned Kate Middleton that she would be in big trouble if a particular incident would happen.

The Duke and Duchess of Cambridge dated for almost a decade before Prince William’s proposal. In a past interview, Middleton’s husband revealed that he had been carrying the engagement ring for weeks even before he popped the big question because he was waiting for the best time.

Prince William also revealed a surprising fact. He admitted that he warned Middleton to keep the ring safe or she would be in “big trouble.”

“I’d been carrying it around with me in my rucksack for about three weeks before that and I literally would not let it go,” Prince William said.

“Everywhere I went I was keeping hold of it, because I knew this thing, if it disappeared, I would be in a lot of trouble.”

Middleton said that she hoped she could look after it because it’s “very, very special.” Prince William then quipped, “If she loses it, she’s in big trouble.”

Prince William and Middleton were talking about the latter’s engagement ring that Prince Charles also used when he proposed to Princess Diana. The piece has a 12-carat oval blue sapphire surrounded by 14 solitaire diamonds. It initially cost $35,478, but its price has increased ten-fold and is now valued at around $380,000.

Prince William and Middleton were spotted on Tuesday joining Queen Elizabeth, Prince Charles, Camilla Parker Bowles, Queen Maxima and King Willem-Alexander at the opening of Royal Ascot. The Duke and Duchess of Cambridge were photographed sharing an umbrella which was reminiscent of Prince Harry and Meghan Markle’s sweet moment at Dubbo during the couple’s royal tour in Australia.

At the event, Queen Elizabeth II was photographed alone while Prince William and Middleton appeared distracted. Her Majesty turned around to the Duke and Duchess of Cambridge who seemed to be disturbed and were caught walking away in a different direction.

The Duke and Duchess of Sussex were missing in the event. Prince Harry and Markle were last seen with the rest of the members of the royal family a few weeks ago at Trooping the Colour.