GPs in the North East have accused the government of wasting billions of pounds of NHS investment and of threatening the existence of the GP system.
In an open letter signed by GPs from across the North East, the group claims that polyclinics planned for the region will destabilise surgeries and inconvenience patients.
The letter reads: "Much has been wasted on ill-considered schemes that may be popular ideas but are not cost-effective in delivering genuine patient care. Examples are NHS Direct, walk-in centres, urgent care teams - not to mention the £12bn spent on a computer system that has not delivered.
"On average a GP consultation costs £21, a single phone call to NHS Direct costs £27, a walk-in centre consultation costs £33 and an A&E attendance £75.
"This confirms general practice as the most cost-effective component of the NHS. Unfortunately, in the government's rush to ensure competition from private companies in the NHS - in the mistaken belief that this drives down costs and improves quality, for which there is no evidence - there is a real risk to present-day general practice."
Dr Roger Ford, secretary for Sunderland Local Medical Committee and Northern Council of the British Medical Association, added: "The establishment of numerous completely new practices, with all the expense of additional overheads, via a tendering exercise is clearly designed to encourage the interest of private companies with shareholders' interests to satisfy."