THE Duchess of Cambridge has given birth to a son, Kensington Palace has confirmed.

The new royal baby - the Cambridges' third child - was born at 11.01am and weighed 8lbs 7oz.

Kensington Palace said in a statement: "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."

The new prince of Cambridge is fifth in line to the throne and a younger sibling to Prince George and Princess Charlotte.

Kensington Palace announced at 8.24am on Monday that Kate had been admitted to the Lindo Wing at St Mary's Hospital, Paddington, London, in the early stages of labour.

She was driven to the private maternity unit before 6am with the Duke of Cambridge at her side.

William and Kate did not know the sex of their baby, so the arrival of a 8lbs 7oz boy was a surprise to them.

The self-proclaimed Royalist Town Crier has announced the birth of the baby prince on the steps of the Lindo Wing, marking the moment by saying "God save the Queen".

He drew cheers from the crowd of royal watchers outside the hospital.

Prime Minister Theresa May said: "My warmest congratulations to the Duke and Duchess of Cambridge on the birth of their baby boy.

"I wish them great happiness for the future."

Kensington Palace said the name of the baby would be announced in due course, and a formal notice of the birth would be posted on the forecourt of Buckingham Palace.

Celebrities and politicians have been sending their best wishes to The Duke and Duchess of Cambridge on social media.

Prime Minister Theresa May sent her "warmest congratulations to the Duke and Duchess of Cambridge on the birth of their baby boy."

"I wish them great happiness for the future," she added.

Mayor of London Sadiq Khan tweeted: "On behalf of Londoners, I want to send our warmest congratulations to the Duke & Duchess of Cambridge on the birth of their baby boy."

Brandon Lewis, chair of the conservative Party, also tweeted his "huge congratulations to the Duke and Duchess of Cambridge."

Shadow education secretary Angela Rayner also tweeted her "congratulations to William & Kate on the birth of their baby boy."

Former world heavyweight champion boxer, Frank Bruno MBE, and Hollywood actress Mia Farrow were among the celebrity well wishers on social media.

Meanwhile, comedian David Walliams quipped: "Prince Harry just got demoted again."