Doctors and nurses' aides will launch a second round of collective action on Thursday to protest the controversial nursing act aimed at improving working conditions for nurses by stipulating their roles and responsibilities.

A coalition of 13 medical workers' organizations, including the Korean Medical Association, warned that Thursday's collective action will be bigger than the previous walkout on May 3.

Dental clinics are set to close on Friday and other doctors plan to shorten consultation and practicing hours.

The number of nursing assistants participating in the collective action is expected to rise to about 20-thousand from ten-thousand in the May 3 walkout. The coalition will also hold rallies across the country. 

Meanwhile, the Korea Nurses Association is calling for a swift promulgation of the act, with its top officials entering a hunger strike on Tuesday.