Polyclinics will not improve patient care or their access to treatment, a survey of NHS consultants has found.
Some 60% of the 1,587 top level doctors who responded to the British Medical Association (BMA) survey disagreed or strongly disagreed that super surgeries would improve the quality of patient care.
Some 42% also did not agree that they would improve patient access to treatment, with about one third undecided on both counts.
And more than 70% of consultants said polyclinics would destabilise local hospitals and GP practices.
The government has hailed plans for large-scale surgeries as the future of healthcare, with longer opening hours, facilities for minor operations and on-site pharmacies.
But critics have argued the era of local family doctors is under threat with a fifth of GP surgeries facing closure.
Analysis by the Conservatives suggests the clinics will result in 1,700 GP practices shutting down.
The BMA survey also found consultants, who include specialists from anaesthetics, geriatrics, ophthalmology and psychiatry, feel hampered in their efforts to do more for patients.
Although 99% agreed consultants should be "leaders and innovators" in clinical practice, 52% said they were being prevented from implementing new ideas.
And 70% said they did not have adequate resources to support them: 63% said they lacked secretarial support, 48% said more IT was needed and a further 48% were unhappy with the level of managerial support.