Prince Charles and Prince Harry. Picture: Supplied

Prince Charles and his wife, Duchess Camilla, are "thrilled" that Prince Harry has got engaged to Meghan Markle.

The 69-year-old heir to the throne and his wife, Duchess Camilla, hope the couple - who announced on Monday morning that they had got engaged earlier this month - will have a "very happy" life together.

READ: Prince Harry and Meghan Markle are engaged

Charles issued a statement on behalf of himself and his 70-year-old wife which read: "We're thrilled. We're both thrilled. We hope they'll be very happy indeed."

And Harry's older brother, Prince William, 35, and his wife Duchess Catherine, also 35, are "very excited" by the news as they get on so well with the 36-year-old actress.

They said in a statement: "We are very excited for Harry and Meghan. It has been wonderful getting to know Meghan and to see how happy she and Harry are together."

Harry's grandparents Queen Elizabeth and Prince Philip are also "delighted" for the couple, who have been together for around 16 months.

A message on the Royal Family Twitter account read: "The Queen and The Duke of Edinburgh are delighted for the couple and wish them every happiness."

Harry, 33, popped the question to the 'Suits' star in London earlier this month and their engagement was announced by Harry's father.

In a statement, Charles said: "His Royal Highness, the Prince of Wales, is delighted to announce the engagement of Prince Harry to Ms. Meghan Markle.

"The wedding will take place in Spring 2018. Further details about the wedding day will be announced in due course."

"His Royal Highness and Ms. Markle became engaged in London earlier this month.

"Prince Harry has informed The Queen and other close members of The Royal Family.

"Prince Harry has also sought and received the blessing of Ms. Markle's parents.

"The couple will live in Nottingham Cottage at Kensington Palace."

Harry was best man when William and Catherine - who have son Prince George, four, and two-year-old daughter Princess Charlotte and are expecting their third child - tied the knot on April 29, 2011.