Junior doctors in England will stage a full walk-out on 26 and 27 April, the British Medical Association said this afternoon.
The announcement marks the latest move in an escalating row between medical professionals and the government.
The planned strikes on 26 and 27 April will be the first time the doctors have refused to provide emergency cover.
The BMA said the all-out strike will last from 08:00 to 17:00 both days.
There have already been three strikes so far in the dispute between the BMA and health secretary Jeremy Hunt, but in all previous industrial actions, junior doctors continued to provide emergency services.
A separate 48-hour strike, from 8:00 on 6 April, will also still go ahead, with emergency cover in place.
The health department slammed the BMA's decision as "desperate and irresponsible".
"This escalation of industrial action by the BMA is both desperate and irresponsible – and will inevitably put patients in harm’s way," a health department spokesperson said.
"If the BMA had agreed to negotiate on Saturday pay, as they promised to do through ACAS in November, we’d have a negotiated agreement by now – instead, we had no choice but to proceed with proposals recommended and supported by NHS leaders."