The Duke and Duchess of Cambridge announced tonight their baby son would be called George Alexander Louis.

William and Kate's baby will be known as Prince George and as third in line to the throne will one day be king.

Kensington Palace said in a short statement: ''The Duke and Duchess of Cambridge are delighted to announce that they have named their son George Alexander Louis.

''The baby will be known as His Royal Highness Prince George of Cambridge.''