Three royal parks including the home of Princess Alexandra are to be shut to stop foot-and-mouth disease spreading to deer herds.
The shutdown, from midnight tonight, will stop public access to Richmond Park, Bushy Park and Hampton Court Home Park, all in south west London.
Restricted access would be granted to residents, including Princess Alexandra, who would only be allowed to use certain gates and must use disinfectants before entering the parks.
The deer herds have bloodlines dating back to the reign of Henry VIII and the decision was taken to prevent them catching the disease, which has threatened to cripple Britain's agriculture industry.
"There is no foot-and-mouth disease among the deer in the royal parks, this is just a precaution," said a Royal Parks Agency spokesman.
"We feel we have to batten the hatches down to protect a treasured herd of deer."
The parks would remain closed until further notice.
Princess Alexandra, her husband Sir Angus Ogilvy, and the 400 pupils of the Royal Ballet School will be among the residents who have to observe the restricted access conditions. Many former royal household officials also have homes within the grounds of the parks.