Here is the official press release the world has been waiting for:
Her Royal Highness The Duchess of Cambridge was safely delivered of a son at 4.24pm.
The baby weighs 8lbs 6oz.
The Duke of Cambridge was present for the birth.
The Queen, The Duke of Edinburgh, The Prince of Wales, The Duchess of Cornwall, Prince Harry and members of both families have been informed and are delighted with the news.
Her Royal Highness and her child are both doing well and will remain in hospital overnight.