Ambulance chief Tim Skelton has defended proposals to merge the Wiltshire service with neighbouring Gloucestershire and Avon, saying the move could benefit patients and staff.

He said the integration would offer the Wiltshire service, which has received the lowest possible performance rating of zero for the last two years, more resources and more flexibility.

But concerns have been voiced by both North Wiltshire MP James Gray and a patient watchdog group. Both fear a merger would lead to Wiltshire's resources being drawn into the urban areas of Bristol and Bath.

On Friday, the chief executives from all three ambulance trusts met with members of the strategic health authority and primary care trusts to discuss the way forward.

They agreed for a detailed review to be undertaken of the impact of either merging the management of the three services, or merging them completely.

A steering group was set up to work out the terms of reference of the review, with the aim of it beginning in March with the results available from April.

Speaking after the meeting, Mr Skelton said: "Because we are a small NHS trust, we feel we would be better to integrate our overheads with another organisation.

"If we could integrate, we would have fewer overheads and create an organisation that is more attractive in recruiting the best staff."

Pointing to operational benefits, Mr Skelton said: "On a typical night we only have 11 ambulances to cover the whole of the county. If there is a big road traffic accident, it can take up a lot of ambulances and leave the rest of the county exposed.

"Integration would offer us greater flexibility. I feel integrating the Wiltshire Ambulance Trust with another body would save money and improve the front-line service for patients."

He said new satellite technology should solve any problem of lack of rural knowledge among ambulance staff and felt it was important that the Wiltshire service retained its identity in the merger.

The amalgamation plans come at a time when the Wiltshire service is failing to meet national targets for response times.

A year ago only 50 per cent of calls were meeting the eight-minute target, and although this has improved dramatically, reaching 73 per cent last month, the number of emergency calls continues to increase.

But Mr Skelton believes the trust's bid for a £600,000 automatic vehicle locating system will allow controllers to pinpoint ambulances and improve ambulance response times.

Mr Skelton said: "We have come a long way in recent months but the 999 calls continue to grow at an alarming rate and we do not get the resources to cope with that. Our income is only £13 million.

"And because we are a NHS trust we have to have systems in place for clinical governance, staff training and recruitment. I am not saying there are not risks, but we cannot afford to stand still."

Mr Skelton added that the plans had been discussed widely with staff and unions.

And he rejected concerns that any amalgamation could lead to the service being dominated by calls from Bristol.

As for concerns about the future of the £7million joint emergency control room in Devizes, which opened in November 2003, Mr Skelton said nothing had been discussed or decided.

He said: "I think we should do a robust analysis to see if things should be done differently. You can never stand still. We always have to look to the future."

Jeff White, secretary for the Association of Professional Ambulance Personnel, said staff welcomed the proposals if it improved the level of service.

Mr White said: "The general consensus is that staff are keen to go along with the merger and keep their identity. If a merger means more vehicles, better equipment and more money it has got to be good. We do not feel resources will be dominated by Bristol."

Unison union representative Simon Andrews cautiously welcomed a merger. He said: "The potential is there to improve services. But I do have concerns that with a merger maybe health issues in Wiltshire might not get the attention they deserve.

"There is a perception in the county that many services go to Swindon, and we do not want rural areas to lose out in any amalgamation."

But members of the patients' watchdog group, The Wiltshire Ambulance PPI (Patient and Public Involvement) Forum, raised concerns about Wiltshire's resources being drawn into Bath and Bristol at a meeting with trust officers.

A forum spokesman said: "The trust acknowledged that there would be a risk to the service in Wiltshire if all the resources were allowed to be drawn into Avon."

He added: "Members asked about the future of the control room at Devizes. The trust also acknowledged that the merger would not necessarily mean the need to have a local control room. However, the advantages and disadvantages would have to be examined."

Two weeks ago MP James Gray met Mr Skelton and told him that he was wholly opposed to the regionalisation of the Wiltshire service. He said the county would be lost in the amalgamation, which would lead to the domination of Bristol.