GP waiting times will "rocket" unless the system is overhauled, research has suggested.
Sick people currently wait an average of 13 days for an appointment with their doctor - an increase from 10 days in 2015.
A survey of 830 doctors by Pulse magazine found one in 10 GP surgeries who replied have average waiting times of more than three weeks for non-urgent appointments.
Proposals from the Conservative Party to increase the number of GPs by 5,000 in the next three years will not be enough to keep up with demand fuelled by a rising population and increased demand for appointments, the publication said.
Dr Chaand Nagpaul, chairman of the British Medical Association's GP Committee, told Pulse: "There is no way any GP can work harder. Eight in 10 GPs say they cannot provide safe care.
"We need to reduce workload.
"If we carry on like this, we won't have any GPs working. GPs are unwilling to put up with intolerable workload.
'Unless the Government takes decisive action, waits to see a GP will rocket to several weeks in the coming years as patient demand continues to rise, and will seriously compromise patient care."
The Conservatives have said their party is investing £2.4 billion more into primary care - and disagree with the findings of the "self-selecting survey".