South Korea’s largest organization of doctors voted in favor of holding a strike on June 18, the first time it’s taking collective action to protest against government plans to reform the medical sector.

The Korean Medical Association said 64,139 doctors, or 90.6% of those who took part in the strike referendum last week, supported the walkout. Lim Hyun-taek, head of the KMA, said in a statement that the group represents 140,000 doctors and 20,000 medical students nationwide.

The new action comes after the nation faced months of disruption in medical services, when trainee doctors at hospitals left work to protest against the government’s decision to increase the number of seats at medical schools. Despite that protest, the government finalized adding some 1,500 places to the nationwide admission quota, the first increase in 27 years.

"We sternly warn the government,” Lim said in the statement on Sunday. "The government must stop the tyrannical policies of the past four months and apologize to the public.”

On the same day before the association’s announcement, Prime Minister Han Duck-soo said the government will not impose any penalties on junior doctors returning to work.