The Prime Minister and politicians' have expressed their concern over news that the Queen is under medical supervision at Balmoral.
Buckingham Palace issued a statement just after 12.30pm saying royal doctors were concerned for the 96-year-old monarch's health.
They said the head of state was comfortable and her royal physicians recommended she remain under medical supervision, as the Prince of Wales, the Duke of Cambridge and the Duchess of Cornwall cleared their diaries and immediately headed to her side.
A Palace spokesperson said: "Following further evaluation this morning, the Queen’s doctors are concerned for Her Majesty’s health and have recommended she remain under medical supervision.