The medical director of Suffolk's GP-led health centre has resigned, calling the project 'a threat to local services'.
Dr Andrew Cornish said it had become 'just another general practice, funded at a higher rate than other surgeries'.
The Crown Surgery, Suffolk PCT's GP-led health centre, will open in Haverhill in June.
Dr Cornish was appointed medical director after The Practice plc, a firm that runs several practices, was confirmed as the successful bidder.
But the £1 million centre will open initially in temporary facilities, which will not feature the extended services Dr Cornish had hoped to see. He took the post believing it would offer X-rays and ultrasound.
Suffolk PCT said these services will be available, but only once the centre moves to a permanent base in three years.
'I could no longer be involved in something in direct competition with other practices,' said Dr Cornish, a partner at the nearby Christmas Maltings and Clemence surgeries.
He said the PCT had just cut £300,000 in funding from PMS practices, but was spending £240,000 a year to rent 'a stack of Portakabins' to house the Darzi centre. 'They will be paid per patient considerably more than other practices,' he said.
Local GP Dr Mary Selby is calling for a public inquiry into the project, which aims to register 6,000 patients from the town within five years.
Julian Herbert, NHS Suffolk deputy chief executive, was 'surprised and disappointed' by Dr Cornish's resignation. The health centre would receive 'different funding' because it opened longer hours and offered more services, he said.
No-one from The Practice plc was available to comment.
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