GREAT Western Ambulance Service has been told to improve its performance or face being replaced in Wiltshire.

The ultimatum has been made by Wiltshire Primary Care Trust which says poor response times cannot be allowed to continue.

The Great Western Ambulance Service was formed in April 2006 following the merger of Wiltshire, Avon and Gloucestershire ambulance services and has struggled to consistently meet national targets in sending ambulances to patients.

The service is funded by Wiltshire PCT and other PCTs in the area. On Tuesday the board of Wiltshire PCT agreed a three-year operational plan to improve services.

It includes working with the ambulance service to improve response times and targets on administering a clot busting drug to heart attack patients.

But the PCT says where improvement is not forthcoming it will explore the use of another provider.

PCT chief executive Jeff James said: "We have a commitment to working with neighbouring PCTs and the Strategic Health Authority to ensure the recovery plan that the ambulance service is creating has its best possible chance of succeeding.

"However, if we should find that it doesn't result in improvements in performance on the ground we would be looking at other providers.

"It's something we would contemplate if it was necessary to get a good ambulance service."

He said if it did happen it would be logical for the PCT to talk to three other ambulance services that border Wiltshire.

John Williams, director of finance at the PCT, said: "Previously we have accepted performance that could be described as indifferent."

A spokesman for the Great Western Ambulance Service said: "We have an action plan agreed with our Primary Care Trust and with the Strategic Health Authority to improve our performance."

The hard line adopted by the PCT comes as six councils, including Wiltshire and Swindon, have decided to form a joint health scrutiny committee to discuss the performance of the ambulance service.

The first meeting will be on February 29.