Updated April 27, 2018 21:08:10

Photo: The young prince is fifth in line to the throne. (Reuters: Henry Nicholls)

The Duke and Duchess of Cambridge have named their new baby son Louis Arthur Charles.

"The baby will be known as His Royal Highness Prince Louis of Cambridge," Kensington Palace said.

The prince, who is fifth in line to the throne, was born on Monday evening (AEST).

He weighed 8lbs 7oz (3.83kg).

Louis is William's fourth name as well as being that of Earl Mountbatten, to whom William's father Prince Charles was particularly close.

Mountbatten was the uncle of Prince Philip, 96, great-grandfather of the new prince.

Charles, heir to the throne, has said it was a great joy to have another grandchild.

William and Kate now have three children: Louis joins Charlotte, 2, and George, 4.

For a boy, the leading bets were for Albert, Arthur, Alexander, James and Philip.

The betting odds indicated just a 5 per cent chance of Louis.

Reuters

Topics: royal-and-imperial-matters, human-interest, family-and-children, parenting, united-kingdom

First posted April 27, 2018 20:07:47