More than 9,000 young doctors, or about two-thirds of the total number of physician trainees in South Korea, walked off the job last week because of the plan, saying the healthcare sector was not short of doctors, and the government should address pay and working conditions first.

Several ministers have threatened the protesters with legal action, including suspending their licences, while also inviting the doctors to hold talks to end the dispute.

Yoon, however, maintained the same hardline stance he took in the face of a strike by truckers in 2022, as the dispute started to disrupt supply chains and threatened to paralyse key industries.

"This is not a matter for negotiations or compromise," he said of the plan, which also includes expanded legal protection for doctors and plans to improve healthcare in rural areas.

"It is difficult to justify under any circumstances the collective action that takes public health and lives hostage and threatens human lives and safety," Yoon said in televised comments, adding that the package of health care reforms included many of the demands of the medical community.

Many Koreans back Yoon's plan, and his support ratings have edged up in recent weeks, ahead of a general election in April. A recent Gallup Korea poll showed 76% support for the plan.

On Tuesday, the health authorities gave nurses the right to perform some medical procedures normally conducted by doctors, as authorities seek to ease the strain on hospital staff.

"We consider it as positive, since the government is giving protection to nurses," said an official at the Korean Nursing Association official, who declined to be named as this was his opinion. The association has yet to issue an official statement.

The walkout has disrupted services at major hospitals, where emergency rooms have turned away patients and some surgeries and other procedures have been cancelled or postponed.

Some senior doctors and private practitioners have not joined the walkout but have held rallies to urge the government to scrap its plan.

Vice health minister Park Min-soo repeated a plea to the young doctors who have joined the walkout to return to work by Feb. 29 so that they can be spared punishment including suspension of licences and possible prosecution and arrest.

Park said the government had conducted a legal review that concluded it had right to limit doctors' actions in the public interest, prompting objections from some senior doctors.

"It is abuse of power. It is a step backward for democracy" Chung Jin-haeng, a Seoul National University medicine professor, said.

In a nod to the one of the protesters demands for more legal protection from malpractice, Health minister Cho Kyoo-hong said the government was speeding up work to legislate what he called unprecedented legal protection for doctors that will allow patients to swiftly get compensation for injuries suffered during medical procedures and doctors to focus on their work.

Reporting by Jack Kim; Editing by Ed Davies, Stephen Coates and Miral Fahmy