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.
The medical staff present were Mr Marcus Setchell, Surgeon-Gynaecologist, Mr Guy Thorpe-Beeston, Obstetrician and Dr Sunit Godambe, Consultant Neonatologist at St. Mary’s Hospital.
The names of the baby will be announced in due course.
The baby is third in the line of succession after His Royal Highness The Prince of Wales and His Royal Highness The Duke of Cambridge. He is styled His Royal Highness Prince [name] of Cambridge.
A formal notice of the birth will be posted on the forecourt of Buckingham Palace.