THE Duke and Duchess of Sussex have named their son Archie Harrison Mountbatten-Windsor.

The couple's @SussexRoyal Instagram account announced: "The Duke and Duchess of Sussex are pleased to announce they have named their first born child: Archie Harrison Mountbatten-Windsor. This afternoon Their Royal Highnesses introduced Her Majesty The Queen to her eighth great-grandchild at Windsor Castle. The Duke of Edinburgh and The Duchess' mother were also present for this special occasion."

The family of three were pictured in a black and white snap showing off baby Archie to the Queen and Philip, alongside Meghan's mother Doria Ragland.

Harry and Meghan's first born, who is seventh in line to the throne, made his world debut with his besotted parents at Windsor Castle on Wednesday.

Proud mother Meghan described him as having the "sweetest temperament", while a delighted Harry called him "our own little bundle of joy".

The duchess added: "It's magic, it's pretty amazing. I have the two best guys in the world so I'm really happy."

As is the custom for royal babies, Harry and Meghan will have shared news of their choice with the monarch before releasing it to the public.

The duke and duchess's son arrived on Monday May 6 at 5.26am, weighing 7lb 3oz.

Harry said, when announcing the birth, that the baby's late arrival had given them longer to decide on a name.

"The baby is a little bit overdue, so we've had a little bit of time to think about it," he said.

Among the bookmakers' favourites were Alexander, Arthur, Albert, as well as James and Philip, while Spencer was a late favourite, but Archie was a surprise choice.