Doctors are to take industrial action for 24 hours in protest at the Government's controversial pension reforms.
Non-urgent cases will be postponed on the day of action on June 21 and further action has not been ruled out.
The British Medical Association (BMA) said it was taking action "very reluctantly" but attacked the Government for going back on a deal on pensions agreed four years ago.
The move followed a big vote in favour of action by doctors.
Dr Hamish Meldrum, chairman of council at the BMA, said: "We are taking this step very reluctantly, and would far prefer to negotiate for a fairer solution.
"But this clear mandate for action - on a very high turnout - reflects just how let down doctors feel by the Government's unwillingness to find a fairer approach to the latest pension changes and its refusal to acknowledge the major reforms of 2008 that made the NHS scheme sustainable in the long term.
"Non-urgent work will be postponed and, although this will be disruptive to the NHS, doctors will ensure patient safety is protected.
"All urgent and emergency care will be provided and we will work closely with managers so that anyone whose care is going to be affected can be given as much notice as possible."
The BMA said doctors will see anyone who is ill, or who believes they are ill, on the day of action, but will not do paperwork.