The landmarks across London were lit in hues of red, white and blue to celebrate the birth of first child of Prince William and Kate Middleton.

The Duchess of Cambridge gave birth to a baby boy, weighing 8lbs and 6oz, at 4.24pm after she was admitted to St Mary's Hospital earlier in the day. The Duke of Cambridge was also present for the birth. The new born is yet to be named but he is styled His Royal Highness Prince of Cambridge, according to Clarence House.

William and Kate's son is third in the line of succession after Prince of Wales and the Duke of Cambridge. The royal and the Middleton families were delighted upon the birth of the future king of England and were quick to express their excitement.

"Both my wife and I are overjoyed at the arrival of my first grandchild. It is an incredibly special moment for William and Catherine and we are so thrilled for them on the birth of their baby boy," Prince Charles said in a statement. "Grandparenthood is a unique moment in anyone's life, as countless kind people have told me in recent months, so I am enormously proud and happy to be a grandfather for the first time and we are eagerly looking forward to seeing the baby in the near future."

Meanwhile, celebrations were also seen hundreds of miles away in Ottawa, Canada, where the Peace Tower on Parliament Hill was lit blue. Prince William and Kate Middleton made their first foreign visit as the Duke and Duchess of Cambridge to Canada after their royal wedding in 2011.

Scroll down to view photos of a lit London and Ottawa signifying with the royal birth while some pictures showcase the excitement of Londoners who thronged the forecourt of Buckingham Palace to get a glimpse of the posted notice formally announcing the birth of a son to Prince William and Catherine.

The London Eye is lit in red, white and blue after Catherine, Duchess of Cambridge gave birth to a baby boy at St Mary's Hospital in central London.REUTERS
The fountains at Trafalgar Square are seen lit blue to signify the birth of a baby boy to Britain's Prince William and Catherine, Duchess of Cambridge in LondonREUTERS
The London Eye is lit in red, white and blue after Catherine, Duchess of Cambridge gave birth to a baby boy at St Mary's Hospital in central London.REUTERS
People gather to see the Peace Tower lit blue to celebrate the birth of a baby boy to Britain's Prince William and Catherine, Duchess of Cambridge, in Ottawa 22 July, 2013.REUTERS
The Peace Tower on Parliament Hill is lit blue to celebrate the birth of a baby boy to Britain's Prince William and Catherine, Duchess of Cambridge, in Ottawa 22 July, 2013. Prince William's wife Kate gave birth on Monday to a boy, who becomes third in line to the British throne, ending weeks of feverish speculation about the royal baby. The couple's first child was born at 4:24 p.m. (1524 GMT), weighing 8 lbs and 6 oz. His name will be announced at a later date but bookmakers favour George and James.REUTERS
A notice formally announcing the birth of a son to Britain's Prince William and Catherine, Duchess of Cambridge, is placed in the forecourt of Buckingham Palace, in central London.REUTERS
A crowd of people try to look at a notice formally announcing the birth of a son to Britain's Prince William and Catherine, Duchess of Cambridge, in the forecourt of Buckingham Palace, in central London.REUTERS