A "workforce crisis" among GPs may result in a need to support doctors thinking of leaving the NHS, a health body has warned.
A group of doctors in Bedfordshire is raising concerns at the Local Medical Committee (LMC) conference.
It has called on the British Medical Association to "urgently look at how these GPs can be supported to operate within a private, alternative model".
The government said it was putting in an extra £2.4bn in GP surgeries.
A Bedfordshire LMC spokesman said the doctors had decided to put forward the motion to the conference on 10 November because of the "increasing pressure on GPs" at a time of "constant increases in workload and chronic underfunding".
'Pressure on GPs'
"We are witnessing a substantial increase in the number of GPs leaving the profession and, in some cases, GP practices closing," he said.
"Many GPs believe that the government's failure to adequately address the severe shortage of GPs and other practice staff is forcing general practice down the route of finding alternative ways to maintain the quality of services patients deserve.
"The intention of the Bedfordshire LMC motion is to raise awareness of these funding issues, the pressure on general practice that politicians have for far too long ignored."
A Department of Health spokeswoman said: "GPs are the bedrock of our health service, but we know that they face real pressure as demand increases and our population ages.
"We have recently set out plans to provide a sustainable solution to the unpredictable costs of indemnity and are investing an extra £2.4bn by 2020 in GP surgeries.
"We want to work with them to overcome these and other challenges and give NHS patients the high-quality care they deserve."
A BMA spokesman said: "General practice is under unsustainable and mounting pressure from rising demand, contracting budgets and staff shortages."