A nationwide union of nurses and medical workers said Saturday that their members have voted to launch a strike next week, calling for a pay raise and the normalization of the crippled medical system amid a prolonged walkout by trainee doctors, its officials said Saturday.

The Korean Health and Medical Workers' Union, which has some 30,000 nurses and medical workers at 61 hospitals as members, said more than 91 percent of its members supported the strike plan, according to the officials.

If an ongoing arbitration by the labor relations committee fails, the unionized workers plan to launch simultaneous strikes Thursday.

The union has been urging the hospitals to swiftly resolve the medical vacuum caused by a monthslong walkout by junior doctors and agree on a 6.4 percent increase in wages.

About 12,000 trainee doctors have left their worksites since late February in protest of the government's plan to boost the number of medical students.

Even if the union decides to strike, nurses and medical workers in essential services will continue to work in accordance with the law, union officials said.