Two out of three doctors are prepared to strike over the government's planned changes to pensions, the British Medical Association (BMA) said on Wednesday.
The union rejected the government's final offer on public sector pensions on Wednesday afternoon, after a preliminary ballot of their members.
The BMA, which has more than 130,00 members, has not taken industrial action since the 1970s when there was a dispute over junior doctors' working conditions, including hours. However, the results of the survey cast the real spectre of unrest unless a compromise can be reached.
In a statement, the BMA council said that it would meet on 25 February to consider balloting for industrial action unless there is a "significant" change in the Government's position.
Dr Hamish Meldrum, Chairman of BMA Council said doctors felt "let down and betrayed", adding "for many this is the final straw".
"Doctors are at the forefront of attempts to save the NHS £20 billion, while trying to protect patient care, are in the midst of huge system reform in England, which is causing chaos in many areas, and are about to enter a fourth successive year of a pay freeze," he said.
"Now on top of this, they are facing wholesale changes to their pension scheme, which was radically overhauled less than four years ago and is actually delivering a positive cashflow to the Treasury.
“Forcing doctors to work to almost 70 is one of our most serious concerns as it could put pressure on doctors to work beyond the age at which they feel competent and safe.
“Industrial action remains a last resort and the government must urgently reconsider its damaging plans. The action we are considering is unprecedented in recent decades. This demonstrates the current level of discontent among NHS staff.”
Nearly two million public sector workers went on strike last November over pension reform, including teachers and civil servants. Several unions are still considering the final offer.
Dean Royles, director of the NHS Employers organisation, said: "Talks are the best way to secure a final deal.
"The NHS scheme talks are complex involving over a dozen unions so it's therefore welcome that, along with a number of other unions, the BMA will continue the discussions.
"It is essential that everyone now hammers out an agreement. Let's concentrate on securing the best sustainable deal, not on industrial action which will always be damaging to patient care."
Responding to the BMA, the Department of Health (DoH) said that the current scheme is "unsustainable" and that the reforms will ensure NHS pensions remain "among the very best".
A DoH spokesman said: "The Government has made an offer which is fair for NHS pension scheme members and for the taxpayer.
"It is disappointing that some BMA members who responded to this poll did not recognise that the agreement reached with the BMA and other NHS unions before Christmas represents the best deal available.
"Doctors and consultants, who are among the highest earners in the NHS, have benefited hugely from the current final salary scheme arrangements compared to other staff groups.
"Under the current scheme, a typical consultant retiring at age 60 will receive a pension of over £48,000 a year for life. In addition they will receive a tax free lump sum of around £143,000 - this equates to a pension pot of over £1.7 million in the private sector. This is unsustainable.
"It is fair that higher earners pay greater contributions relative to those on lower and middle incomes. Lower earner members should not be footing the bill, that is why we have protected those on low salaries - there will be no increase in contributions in year one for those whose pay is less than £26,557.
"The reforms to public service pensions will ensure that NHS pensions remain amongst the very best.
"The Government has made clear that this is our final position on the main elements of scheme design - it is a fair and affordable deal for both staff and the taxpayer."
Possible industrial action from BMA members is a further blow for the government, who had hoped to move ahead on public sector reforms.
Unite, the Public and Commercial Services union and Unison are also disputing proposed changes, as are the teaching unions, the NUT and NASUWT.