Junior doctors in England will strike on five days from 24 to 28 February, in an ongoing dispute with the government about pay.
The British Medical Association (BMA), which represents junior doctors, wants a 35% pay increase - a proposal previously rejected by ministers.
Many routine hospital services are likely to be disrupted or cancelled.
The government said it wanted to find a "reasonable solution" and is prepared to "go further" on a pay offer.
Junior doctors received a pay rise averaging nearly 9% this financial year - and during talks at the end of 2023, the option of an extra 3% on top of that was discussed.
But those talks ended in early December without a deal being reached.
'Credible offer'
The BMA said the government had "failed to to meet the deadline to put an improved pay offer on the table".
Junior doctors committee co-chairs Dr Robert Laurenson and Dr Vivek Trivedi said: "We have made every effort to work with the Government in finding a fair solution to this dispute whilst trying to avoid strike action."
They added that they believed the forthcoming strike could still be called off if a "credible offer" was made.
The BMA previously said the pay increase it was calling for would make up for what it said had been below-inflation rises since 2008.
Health secretary Victoria Atkins said: "This action called by the BMA Junior Doctor Committee does not signal that they are ready to be reasonable.
"We urged them to put an offer to their members, but they refused.
"Five days of action will put enormous pressure on the NHS and is not in the spirit of constructive dialogue."
This will be the 10th strike by junior doctors since March 2023. It will follow a six-day strike by junior doctors in January, the longest in the history of the NHS, which saw about 100,000 appointments cancelled.
Nearly half of NHS doctors are junior doctors - a group that spans those just out of university through to some who have 10 years or more experience.
The BMA is also balloting junior doctors on further industrial action beyond this strike.
More than 1.2 million medical appointments have been cancelled since December 2022, due to strikes by NHS workers, including nurses, paramedics and consultants.
The union is currently in talks with the government about a fresh pay deal for consultants, after rejecting the most recent offer.
