The organiser of a popular speedway venue in North Northumberland says it is under threat because of a shortage of medical cover.
St John Ambulance has withdrawn support from Berwick's Shielfield Park venue just over two weeks before the season is due to start.
The charity says there are not enough volunteers to help staff the event.
Berwick Bandits promoter Peter Waite says he has tried other charities, but they are unable to help.
He said: "St John Ambulance say they've done a feasibility study and they can't cover us to a satisfactory standard.
"We've tried the Red Cross, St Andrews and various private companies, but they are all contracted out.
"The problem is that Berwick's an hour and a half from Newcastle, and the event's on Saturday evening, which just isn't a popular time."
John Purvis, of St John Ambulance, said: "We haven't the staff in North Northumberland to cope with the event at the moment.
'Volunteer shortage'
"Our decision is based on the fact we can't fulfil a contract, and we won't enter into a contract we can't fulfil.
"There's a lack of volunteers in the organisation at the moment. We do have a recruitment drive under way, but nothing that will be ready soon enough to help cover the speedway at Berwick."
Mr Waite says he is looking at the possibility of buying an ambulance, but that would cost more than �20,000.