A letter from Dan Poulter, under-secretary of state at the Department of Health, was sent to the chairmen of 19 NHS trusts which belong to the South West Pay and Terms and Conditions Consortium.
The organisation, which includes hospitals in Poole, Gloucester, Bristol, Bath, Salisbury, Taunton and Yeovil says it has come together to deal with unprecedented economic challenges.
However, unions representing NHS workers have voiced fears it is simply a tool to drive down terms and conditions. The letter from Dr Poulter was written following a meeting with MPs from the region who had expressed concerns over the aims of the SWC.
Dr Poulter writes that the Government supports the use of "existing statutory flexibilities" for the benefit of patients. He said: "We also believe that significant benefits can be achieved from trusts coming together to achieve economies of scale in areas such as procurement and back office functions."
He adds that: "Nonetheless we understand that most NHS employers believe that national contracts of employment [under Agenda for Change] can provide advantages for both employers and staff, provided they remain affordable and fit for purpose."
Most importantly for the SWC, Dr Poulter adds that its "priority is to continue to develop the Agenda for Change system and ensure national terms of conditions for NHS staff remain fit for purpose to support the recruitment and retention of good quality staff in the most cost-effective and efficient way".
The creation of the SWC, which health trusts had to pay £10,000 to join, has been controversial from the onset.
Discussion documents from the SWC emphasise that "absolutely no proposals" have been put forward.
However, the papers do detail a number of "staff cost reduction potential opportunities". These include asking people to work extra hours for no extra pay.
The SWC said its research suggested 6,000 NHS jobs in the West could be safeguarded by trusts adopting a number of the recommendations.
Chris Bown, chairman of the SWC, said the current economic circumstances were forcing trusts to act. He said: "Existing legislation permits NHS trusts freedoms in how pay, terms and conditions are arranged at a local level.
"The consortium was established to explore ways in which these existing freedoms may be used to support services.
"This remains the case."