The Princess Royal has been admitted to hospital after she suffered minor injuries and concussion on her estate in Gloucestershire, Buckingham Palace has said.
Princess Anne, 73, is expected to make a full and swift recovery after an incident at her Gatcombe Park estate, a statement said.
She remains in Southmead Hospital, Bristol, "as a precautionary measure for observation".
"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," the statement added.
The cause of the injury is unconfirmed, but it's understood to be consistent with a potential impact from a horse’s head or legs.
The Princess Royal had been expected to begin a visit to Canada at the end of this week.
Canadian media had reported she was due to take part in a ceremony at a war memorial in Newfoundland.
During the recent D-Day commemorations Princess Anne met veterans and their families at the Bayeux War Cemetery in France.
Princess Anne has been known as one of the most hard working royals, carrying out many engagements.
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