Unionized health care workers have begun a nationwide strike on Thursday despite the government sending a message of warning that it might consider taking actions against the protest, dismissing it as "merely political."

The Korean Health and Medical Workers' Union (KHMU) is demanding the Korean government to hire more medical personnel and improve their working conditions. However, the Health Ministry says it's hospitals, not the government who should negotiate with the workers.

"However, justification must be secured when it comes to staging strikes. It's questionable whether it is justified this time. Since what they demand is labor-management issues, it is right for the union to negotiate with their management, not demand government policies,” Second Vice Minister Park Min-soo also said in an interview on Wednesday.

“The government will also consider issuing an order to return to work,” Park added. According to Article 59 of the Medical Law, the Minister of Health and Welfare can order medical workers to return to work forcibly if their strikes cause a severe crisis for the public.

The government also criticized the timing of the KHMU's protest, as it coincides with another major nationwide strike by the Korea Confederation of Trade Unions, the more militant of the nation's two largest umbrella labor organizations.

"It is not right to force the government to announce an improvement plan in time for the KCTU's strike. Even now, the KHMU should withdraw its intent to join the KCTU strike and take care of patients," said Health Minister Cho Kyu-hong.

The medical workers' protest also faces criticism from other medical organizations, who say that it endangers patients' lives.

The Health and Welfare Medical Solidarity, which includes the Korean Medical Association, the Korean Dental Association and others, said at a press conference Wednesday that "the large number of health care workers walking out of medical sites could threaten patients’ lives. The union should reasonably resolve pending issues through sufficient dialogue and negotiations with the government, not a general strike that threatens people's lives."

To minimize confusion in the medical field caused by the strike, the Ministry of Health and Welfare formed a team to monitor the situation.

Essential personnel in charge of tasks directly related to patients’ lives, such as emergency rooms, operating rooms, intensive care units, delivery rooms and neonatal rooms have opted not to participate in the strike.

"Emergency medical treatment measures have been prepared to minimize confusion. A system has been established in consultation with local governments, the Korean Hospital Association and medical institutions to maintain essential medical services such as emergency rooms and operating rooms. The government also plans to deploy alternative personnel in an emergency,” said Minister Cho said.

Meanwhile, the Ministry of Health and Welfare raised its health and medical disaster crisis alert on Thursday from "attention" to "caution" following the start of the strike. In response to the escalation of the crisis alert, the government will form an emergency medical treatment countermeasure headquarters in cities, provinces, counties and districts to respond to disruptions in the medical industry.