One in five doctors believe that patient safety is being "compromised" due to staffing problems, a new poll has found.
An annual census of British doctors found that more than half of all consultants and two thirds of trainees reported frequent gaps in junior doctor rotas.
And 20% said that such gaps are causing significant problems for patient safety in hospitals.
Only 2% said rota gaps have no impact on patient safety, according to the census conducted by the Royal College of Physicians of London (RCP) on behalf of the Federation of the Royal Colleges of Physicians.
The survey of more than 8,500 medics also found that consultants and trainees are working around 10% more than their contracted hours.
This equates to trainees working an extra six weeks and consultants an extra month unpaid a year, doctors' leaders said.
More than a quarter of junior doctors (27%) said that if they could turn back time, they would take a medical job outside the NHS and 31% said they would seek a job outside medicine.
Meanwhile the number of consultants working less than full time rose to 23% while a third of the current consultant workforce are predicted to reach their intended retirement age in the next decade.
Commenting on the census, RCP president Professor Dame Jane Dacre (pictured) said: "Sadly the census confirms our fears that the demands on doctors are increasingly untenable.
"Unfilled vacancies and rota gaps, alongside rising numbers of patients, are impacting patient safety and badly affecting doctors' morale.
"With increasing numbers of consultants looking to retire in the next 10 years and our trainees expressing concerns about their wellbeing, we are facing the perfect storm.
"Both short and long-term action needs to be taken if we want to protect patient safety and make medicine the rewarding career it should be."
A Department of Health and Social Care spokeswoman said: "We have recently announced the biggest ever increase in training places for doctors, including five new medical schools - as well as measures designed to retain and attract staff back to the NHS such as new arrangements to help staff improve work-life balance, a Homes for Nurses scheme, and a well-deserved pay rise for over one million NHS staff.
"To secure the future of the health service as it approaches its 70th birthday, we have increased NHS funding by an average 3.4% per year, which will see the NHS receive £20.5 billion a year in real terms by 2023."
Copyright (c) Press Association Ltd. 2018, All Rights Reserved. Picture (c) Royal Colleges of Physicians / PA Wire.