Trainee doctors in South Korea began submitting their resignations en masse Monday in protest of a government medical policy, causing reported delays in surgeries and other treatments at hospitals. Doctors’ groups and the government have been squabbling over a government plan to increase the number of medical school admissions by 2,000, starting from next year.

Health authorities say it’s urgent to have more doctors considering South Korea’s fast-aging population. They say the number of doctors in the country relative to the size of the population is among the lowest in the developed world.