The Korean Health and Medical Workers' Union is set to launch a two-day general strike from Thursday demanding an expansion in medical personnel.

The union said on Wednesday that it will begin with pre-strike rallies nationwide in the evening, with anticipation for the protest already causing disruptions, including delays in surgery schedules, at some hospitals.

The union comprises some 85-thousand members including nurses, nursing aides, medical technicians, pharmacists, therapists and care workers, 45-thousand of whom will participate in the collective action, while essential personnel such as those in emergency rooms will not.

The union is demanding that standards be set on the adequate workforce level for each occupation, as well as an increase in the number of doctors, clarification of the scope and boundaries of duties and an expansion of a comprehensive state system for nursing and caregiving.

Starting with pre-strike rallies nationwide on Wednesday evening, protesters will gather in Seoul on Thursday while walkouts will also take place in Busan, Gwangju and Sejong on Friday.

None of the top five hospitals in Seoul are taking part in the strike but many high-level general hospitals are expected to join, with the National Cancer Center dropping all scheduled surgeries for the two days and Pusan National University Hospital reducing the number of hospitalized patients.

The union will monitor developments in negotiations with the government and hospitals during the two days before deciding its next course of action.