Thurrock Council has criticised NHS England's "dreadful" proposals to merge the 5 clinical commissioning groups (CCGs) in south and mid-Essex.
Initial discussions have been held with the various CCG boards, including Thurrock CCG, about a potential switch to create a single executive structure, with a view to then forming a single CCG in the near future.
Thurrock Council fears the loss of local accountability and strong existing partnerships, together with the varying needs and combined size of the 5 affected areas, mean the proposals are flawed.
Leader of Thurrock Council, Cllr Rob Gledhill said: "We understand the need for the NHS and all public sector bodies to work as efficiently as possible, but that should not be to the detriment of residents who rely on the vital services our local CCGs are involved in providing.
"Creating a single CCG responsible for commissioning health services for 1.2milllion people across south and mid Essex would not only be a huge challenge because of the sheer size of the area, but would result in the loss of local accountability and would be a real waste of the excellent local partnerships that have been formed.
"By taking a more centralised approach, we also fear that the different needs of patients and local priorities in the 5 areas would not be fully taken into account.
"We would strongly urge NHS England to think again about these dreadful proposals to avoid irreparable damage to a health service we are all very proud of."
Cllr Sue Little, chair of Thurrock Health and Wellbeing Board, intends to raise the concerns at a meeting of the Mid and South Essex Sustainability and Transformation Partnership (STP) chairs tomorrow (Thursday 11 July).