“The death of my beloved mother, Her Majesty The Queen, is a moment of the greatest sadness for me and all members of my family,” said the monarch’s son, King Charles III.
Flags at Buckingham Palace and Downing Street have been lowered to half mast.
News emerged early Thursday afternoon that doctors treating the 96 year-old monarch were concerned about the state of her health.
The Queen was surrounded by her children and grand-children when she passed away.
An official plan, known as Operation Unicorn, will now be used to coordinate the passing of the Queen in Scotland.
Hundreds of people have started to gather at Buckingham Palace with some already laying floral tributes.
This is a breaking news story - updates to follow.