The Royal Ascot meeting in June will not go ahead with spectators present.
If the week-long meeting is able to go ahead in some form, the public will be banned due to the ongoing public health emergency.
The event will only be able to take place behind closed doors with government approval.
The Queen and her family will likely not be present at the meeting as they will be keen to set an example.
A racecourse spokesperson said: “For public health and safety reasons we have reached the difficult but unavoidable conclusion that Royal Ascot 2020 (Tuesday 16th – Saturday 20th June) will not be able to take place as an event open to the public.
“It may prove possible to run the Royal Ascot races behind closed doors, dependent on Government and public health policy and the approval of the British Horseracing Authority for us to re-start racing.
“This would be for the benefit of the industry, our valued partners and suppliers and our television audiences at home and internationally. Planning for this is now our complete focus and we will update on progress as and when we can.”
The Epsom Derby, another race meeting attended each year by The Queen, has also been called off.
It has been touted that the Derby could be rerun at a later date.
