The Princess Royal is in hospital after suffering minor injuries to her head and concussion when it is believed she was kicked by a horse on her Gatcombe Park estate.
Anne, a skilled horsewoman who competed in the 1976 Montreal Olympics, was walking on her Gloucestershire estate on Sunday evening when the incident happened.
An air ambulance and emergency services were despatched to the estate and, after being given medical care at the scene, the princess was transferred to Southmead Hospital in Bristol by road for tests, treatment and observation.
Buckingham Palace said in a statement: “The Princess Royal has sustained minor injuries and concussion following an incident on the Gatcombe Park estate yesterday evening.
“Her Royal Highness remains in Southmead Hospital, Bristol, as a precautionary measure for observation and is expected to make a full and swift recovery.
“The King has been kept closely informed and joins the whole royal family in sending his fondest love and well-wishes to the princess for a speedy recovery.”
Although the exact cause of the injuries is unconfirmed, Anne’s medical team have said her head injuries are consistent with a potential impact from a horse’s head or legs.
It is understood the princess was walking within the protected perimeter of Gatcombe Park estate when the incident occurred, and no other individual is believed to have been involved.
Her husband, Vice Admiral Sir Timothy Laurence, who was on the estate at the time, accompanied her to hospital.
The spokesman added: “Her Royal Highness is receiving appropriate expert care. No further details are being shared at this stage.
“Her Royal Highness will remain in Southmead Hospital unless or until her medical team advise otherwise.”
The princess’s accident is the latest health upset to the hit the royal family this year, with both the King and the Princess of Wales diagnosed with and undergoing treatment for cancer, and Sarah, Duchess of York, having skin cancer.
Anne will now miss several engagements this week, including the state banquet for the Japanese State Visit on Tuesday and an overseas tour to Canada, which was due to start this weekend.
“The Japanese State Visit will go ahead as planned, though sadly Her Royal Highness will be unable to attend the State banquet tomorrow.”
Anne is a key member of the King’s slimmed-down working monarchy, and has played an important role as she stepped up in support of Charles amid his condition.
The princess, often dubbed the hardest-working royal, is known for her no-nonsense approach and her commitment to royal duty.
Anne won the individual championship at Burghley in 1971, and was voted BBC Sports Personality of the Year.
In 1976, she took part in the Montreal Olympics as a three-day eventer with the British equestrian team.
The princess survived an attempted kidnapping in 1974 when a gunman tried to abduct her and then-husband Captain Mark Phillips as they were driven along The Mall to Buckingham Palace.
She kept her cool, and when the gunman, Ian Ball, told her to “Come with me for a day or two” because he wanted £2 million, she replied it was not “bloody likely, and I haven’t got £2 million”.
