Doctors in England will strike in the run-up to Christmas, the British Medical Association (BMA) has confirmed.
Resident doctors, formerly junior doctors, will walk out from 7am on 17 December until 7am on 22 December.
The latest strike has been blamed on the "continuing failure of the government to make a credible offer on jobs or pay" by the BMA.
Health Secretary Wes Streeting condemned the move as "cynical", and accused the union of trying to turn medics "into the Grinch who stole Christmas".
Experts expect pressure on services to be "intense" amid rising flu cases and staff sickness, but medics say they have been left with "no choice".
Dr Jack Fletcher, chair of the BMA's resident doctors committee, said: "With the government failing to put forward a credible plan to fix the jobs crisis for resident doctors at the same time as pushing a real terms pay cut for them, we have no choice but to announce more strike dates.
"However, these do not need to go ahead. Gradually raising pay over a few years, and some common-sense fixes to the job security of our doctors, are well within the reach of this government."
Mr Streeting said the BMA had "clearly chosen to strike when it will cause maximum disruption, causing untold anxiety".
"Patients and NHS staff deserve better than this cynical attempt to wreck Christmas," he said.
"After a 28.9% pay rise, the government offered to create more jobs and put money back in resident doctors' pockets. The BMA rejected it out of hand, refused to put the offer to its members, blocking a better deal for doctors.
"Now, without a single conversation with the government, they're threatening more strikes at the busiest time of the year."
Mr Streeting added that it was "time for resident doctors to stand up to the BMA and say that enough is enough".
"These strikes are in no one's interest and there is no moral justification for them," he said. "Resident doctors should ignore the BMA's attempts to turn them into the Grinch who stole Christmas."
Previous resident doctor strikes took place from 25 to 30 July and 14 to 19 November.
The cost of strike action
November's industrial action was the 13th strike since March 2023. The summer walkout was estimated to have cost the health service £300m.
"Everyone knows in the run-up to Christmas we need all hands on deck," said Daniel Elkeles, chief executive of NHS Providers.
"It's really important to be able to discharge as many patients as possible, so that where appropriate, they can be at home with their loved ones.
"We need to ensure there's the hospital capacity too to deal with the additional demand that always comes at this time of year. That's going to be even more challenging now."
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Rory Deighton, acute and community care director at the NHS Confederation, said: "With winter now upon us, flu levels surging, and staff sickness expected to rise, pressure on services will be intense."
Mr Deighton added that the walkout could lead to "thousands of cancelled appointments and operations".
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