Ambulance service bosses have come under fire after attempting to backtrack on previous claims that plan to centralise maternity services in Carlisle are clinically unsafe.

It was revealed by the News & Star yesterday that Derek Cartwright , chief executive of the North West Ambulance Service , had written to the Success Regime on December 19, the last day of the consultation, expressing serious concerns about the proposal to remove consultant-led maternity from Whitehaven.

He said transfer times quoted by the Success Regime had been underestimated, that the plans fail to meet vital guidance on emergency caesareans and were not "clinically safe".

However, after the letter was made public, NWAS quickly backed down, saying it now fully supports the option to remove consultants and leave women in west Cumbria with only a midwife-led unit.

In a statement, released by NWAS following discussions with the Success Regime, a spokeswoman said it has now been given assurances about the issues raised. She added: “Now assured, NWAS fully supports the stated preferred approach set out in option two of the consultation document in relation to maternity services.”

But the response has angered both campaigners and union chiefs, who feel the claims are too strong to simply dismiss.

David Atkinson, of Unison, said their members continue to have serious concerns about the issues raised by Mr Cartwright in his initial letter and called on him to explain what assurances have been given.

"We have no idea what these reassurances are and it's extremely worrying that these aren't being made clear to staff. Unison members still have real concerns about the proposals," he said.

Mr Atkinson added that if they fail to reassure staff, Unison would consult its members - working in both the ambulance service and hospitals - about what to do next, and couldn't rule out action.

When asked for more detail about the reassurances, NWAS said it felt the Success Regime's preferred option was the most sustainable.

They added that "escort arrangements" would now be put in place when transferring higher risk patients to Carlisle, and that work would be done to ensure emergency caesarean targets would be met.

But campaigners are incredibly skeptical about quick change of stance by NWAS, and asking how, when Mr Cartwright said it was clinically unsafe to transfer women to Carlisle and that the times stated by the Success Regime were wrong, this has suddenly been resolved.

Lynne Davies, of the We Need West Cumberland Hospital campaign group, said patients will not feel reassured.

She told the News & Star: "At a time when the public has little confidence in decision makers, the fact this chief executive has made a statement in December and withdrawn it less than two months later will lose any trust we had. Its a disgrace."

Retired consultant Mahesh Dhebar added: "Now it has been proven beyond any shadow of doubt that transfer of consultant-led care from West Cumberland Hospital to the Cumberland Infirmary is unsafe.

"Now hospital consultants should come out openly and state what they really think. They owe the truth to the public of west Cumbria."

Mr Cartwright is not the first health service employee to raise concerns about the maternity plans. Several consultants, including obstetricians, dozens of GPs and local midwives have all spoken out.

Even Cumbria's Police and Crime Commissioner, Peter McCall, has gone public with his concerns, saying ambulance crews are already so overstretched that police are being called out to assist.