Prince Harry and Meghan Markle have issued a fresh statement defending their decision to formally adopt the prince and princess titles for their two children, Archie, three, and Lililibet, 21-months.

The Duke and Duchess also insisted that the matter had been ‘settled for some time’ with King Charles – despite only being revealed by the couple yesterday.

They said: “The children’s titles have been a birthright since their grandfather became Monarch. This matter has been settled for some time in alignment with Buckingham Palace.”

Yesterday, Harry and Meghan released a surprise statement confirming their daughter had been christened in a private ceremony in California. But hidden within the statement was their decision to adopt the titles for their children, as the 21-month-old was referred to as “Princess Lilibet Diana”.

A spokesperson for the couple told People magazine: “I can confirm that Princess Lilibet Diana was christened on Friday, March 3 by the Archbishop of Los Angeles, the Rev John Taylor.”

It marks the first time the couple have referred to either of their children as either prince or princess, settling the long debate on the matter.

The King is said to have told Prince Harry that his children would be allowed to be called prince and princess in a ‘private conversation’ after the Queen’s funeral last year.

But their 21-month-old daughter Lilibet saw her royal title of ‘Princess’ used formally for the first time yesterday when the couple told the world she had been christened in California without Charles, Camilla, William, and Kate present.