The future of St Helier is in jeopardy after it became the frontrunner for plans to close an accident and emergency (A&E) and maternity unit.

One hospital out of the four in south-west London is likely to have both front-line services axed as part of an NHS review.

St George’s Hospital has already been ruled out of any cuts, meaning either St Helier, Kingston or Croydon University hospitals could lose the key departments under the proposals.

St Helier Hospital, whose merger plans with St George’s collapsed last month, is widely thought to be the victim of the cuts as it has the smallest A&E and obstetrics departments with the fewest users.

Last month an NHS London study of the four hospitals found only St Helier – which overspent by £12.6m this financial year and must cut £57m by 2016-17 – would not be “financially viable” in three years.

Politicians and campaigners have vowed to fight to save the hospital’s services, after an NHS review recommended losing the front line services at one of south-west London’s four hospitals.

Geoff Martin, of health watchdog London Health Emergency, said all the signs were the announcement would lead to “the cynical destruction of St Helier hospital”.

He said: “This is not scaremongering, we are talking about facts. It is about whether the hospital is seen as viable, and it is clear St Helier is not seen as viable.

“It has a huge deficit that must be cut. Health bosses will look to do that by removing its major services like maternity and A&E.”

St Helier chief executive Matthew Hopkins did not accept St Helier was the most likely hospital to face the proposed cuts.

He said both A&E and maternity were among the best in the country and busy services that could be expanded and would have greater access to finance if kept.

He said to reduce well-performing services that had been built up over time would be “a tragedy”.

The changes to services have been recommended by clinicians carrying out the NHS Better Service Better Value review of how health services are delivered in the region.

Doctors, nurses and other health professionals, including those at St Helier Hospital, leading the review concluded better services could be provided at three better-staffed emergency departments in south-west London rather than the current four, each with an integrated urgent care centre.

A fourth stand-alone urgent care centre – which would provide emergency but non-life-threatening care treating up to 70 per cent of patients currently seen at A&E – is also proposed, most likely at the hospital site that loses its A&E.

On Tuesday the Department of Health announced St Helier was to receive £5.5m for a major expansion of its urgent care centre.

The review also recommended three maternity units at the hospitals with A&Es, with clinicians not ruling out the possibility of a stand-alone midwife-led unit elsewhere.

Carshalton and Wallington MP Tom Brake said he feared maternity services at St Helier would be targeted – but he could not see how the area could survive without its A&E.

He said: “It is clear that because St Helier has the smallest maternity unit, it must be the most vulnerable as it could be seen as the easiest to redistribute work from.

“What is clear at the moment is from the anecdotal evidence I have the St Helier A&E department is extremely busy all the time, and I can see no way that the other hospitals could absorb those numbers.”

Councillor Sean Brennan, leader of Sutton Council, said: “This is yet another blow for the people of Sutton who have long been concerned about the future of our emergency and maternity services.

"It is an even more disturbing prospect given the recent, now collapsed, attempt to merge it with St George’s Hospital and we are asking serious questions of NHS South West London.

“Sutton has one of the highest birth rates in London, so it does not make sense to consider removing our local services.

"Maternity services at St George’s are already full to capacity and the prospect of having to travel to either Kingston or Tooting for A&E services is something that deeply concerns residents.

“St Helier is very well-used, providing vital services for people in Sutton and beyond.

"I will be making sure NHS South West London understands this and we will continue to fight to keep these most important services open.”

Sutton and Cheam MP and Paul Burstow – who has been criticised for allowing St Helier to come under threat while in the influential position of Care Services minister – said the arguments made for reducing the number of units were not convincing.

He said: “I have grave doubts about the process.

Announcing plans to close an A&E and maternity unit are bound to scare people. The case for change has not been made.”

St Helier chief executive Matthew Hopkins said: “It is important to make sure all four hospitals are providing the best quality of care.

“With the current way the NHS is being funded there will have to be changes and a degree of consolidation.”

But he said there was strong evidence St Helier’s high level of care could be expanded to take on more patients as part of that consolidation process.

He said the hospital could not predict the outcome of the review, but would continue to provide quality and cost improvements at the hospital, and work with GPs, MPs, Sutton Council and other organisations to present the case for services at the hospital to be maintained, and to find a viable plan for the hospital to reach foundation status.

Dr David Finch, local GP and joint medical director for Better Services Better Value, said: “These are clinical recommendations only. No decisions have been made and our recommendations will be subject to full public consultation.

“By centralising maternity services we can help ensure every mother has one-to-one midwife care and a senior doctor on hand in case of emergencies.

“By centralising highly trained and specialist doctors and nurses we can treat more patients in bigger units and separate planned care from emergencies, making sure safety and quality is the best it can be for everyone.”