AceShowbiz - British royal Prince Harry and Meghan Markle, Duchess of Sussex have named their newborn son Archie Harrison.

The couple welcomed its first child in the early hours of Monday, 06, and introduced the baby boy to the world at a special photocall at Windsor Castle on Wednesday.

The Duke and Duchess stopped short of sharing their child's chosen name at the time, but hours after taking their son to meet his great-grandparents, Queen Elizabeth II and Prince Philip, Duke of Edinburgh, they made a formal announcement via their official Instagram page, ending days of feverish speculation.

"The Duke and Duchess of Sussex are pleased to announce they have named their first born child: Archie Harrison Mountbatten-Windsor."

The news was accompanied by a casual black-and-white photo of the happy couple with the Queen and Prince Philip, with Meghan's mother, Doria Ragland, also on hand for the private gathering.

"This afternoon Their Royal Highnesses introduced Her Majesty The Queen to her eighth great-grandchild at Windsor Castle," the post continued. "The Duke of Edinburgh and The Duchess' mother were also present for this special occasion."

Archie is the seventh in line to the throne.

During their first photocall as a family of three, former actress Meghan admitted the first two days of motherhood have been "magic" as their son has "the sweetest temperament."

"It's pretty amazing. I have the best two guys in the world, so I'm really happy," she smiled. "He's just been a dream."

Harry and Meghan announced they were expecting in October (2018), five months after they wed in St. George's Chapel at Windsor Castle, England.