Doctors are set to take industrial action for the first time in 37 years, despite last-ditch attempts from ministers to dissuade them.
Health Secretary Andrew Lansley pleaded with doctors not to take part in the day of action which is being held in protest over the Government's controversial pension reforms.
He urged doctors not to participate in the "pointless" strike, warning them it will achieve nothing. NHS leaders also said patients should not be dragged into the dispute.
The British Medical Association (BMA) said its members did not want to participate in the day of action but feel that there is "no other option left" to make their voices heard.
The BMA announced the action last month after it accused ministers of pressing ahead with "totally unjustified" increases to pension contributions and a later retirement age for doctors even though a deal on pensions was agreed four years ago. The union announced the move after a ballot of more than 100,000 doctors showed a clear majority in favour of protests on a high turnout of 50%.
All non-urgent work will be postponed, the BMA said, adding that although the action will be disruptive, doctors will ensure patient safety is protected. Doctors will see anyone who is ill, or who believes they are ill, on the day of action but will not do paperwork. Accident and emergency departments and maternity services will run as normal, and tests for critical conditions such as cancer will be still available. But some non-emergency hospital clinics, outpatient appointments and planned surgery may be postponed.
GP practices will also remain open but some may postpone routine appointments which can be rearranged for another day.
Speaking on ITV's Daybreak, Mr Lansley accused the BMA of wanting a pension deal which would decrease those of lower paid NHS staff. He said: "We needed something that was fairer for other NHS staff as well, the contributions do need to be properly progressive and they do need to reflect the highest paid paying a greater proportion into their pensions overall.
"We had a pension scheme in the NHS where, quite often, the highest paid got twice as much back, by way of pension benefits, than lower paid. I did set out to make sure that low paid and medium paid staff in the NHS did not lose out and that meant that the higher paid paid more. I'm afraid we are in a position where the BMA are out on their own and what they seem to be aiming for is to try and change things back so they get more and nurses and porters and others in the NHS get less."
He added: "I know doctors don't want to go on strike. I hope they don't. I think if they have an argument and they're angry, they're angry with the Government and that's our job to represent the taxpayer and the public interest, and maybe we will have that argument. But I can't see why anybody thinks there is any benefit in penalising patients. It won't serve any purpose whatsoever."