(Bloomberg) -- South Korean trainee doctors walked off the job from Tuesday in a move set to slow the delivery of health care, in protest of a government plan to drastically increase spots at medical schools to reverse a shortage of physicians.

More than 1,000 trainee doctors have indicated they plan to resign and some have not reported to work Tuesday, Yonhap News reported. The extent of the walkout is not yet known but it has caused some hospitals to delay or postpone surgeries.

President Yoon Suk Yeol’s government plans to increase the number of slots at medical schools from next year by 2,000 from the current 3,058 to alleviate a shortage of doctors, which ranks among the worst among developed countries. It says the move will add medical professionals to more parts of the country and in more fields, which will be needed as the country is facing a demographic crisis with one of the world’s fastest aging populations.

Polling shows that about 75% of the public supports the move that could help reduce waiting times and increase access to the health care system. South Korean doctors also rank as some of the best paid in the world and could see their earning power drop if there are more doctors to see patients.

Organisation for Economic Co-operation and Development countries showed the annual average gross income of self-employed specialists was 6.8 times more than that of the average worker in South Korea as of 2021, which is widest gap among OECD member countries.

The doctors said the move to increase spots at medical schools would not address fundamental problems such as difficult working conditions, a lack of specialists in fields seen as lower paying and a concentration of doctors in urban areas.

About 2,700 trainee doctors at five major general hospitals, including Seoul National University Hospital, said they planned to submit resignation letters Monday and walk off the job Tuesday. But the number of resignation letters has been for less than half of the group, Yonhap News reported, indicating the extent of the labor action may not be as widespread as earlier anticipated.

Four of the five hospital groups where the trainee doctors threatened to walk off the job said they were still in the process of counting workers scheduled for duty. The Catholic University hospital group, officially known as Seoul St. Mary’s Hospital, said a walk out has happened but would not give numbers on doctors who did not report.

The government has called on the trainee doctors to report to work and has a powerful weapon in the fight, because it could use the Medical Services Act to revoke the licenses of doctors over prolonged labor actions that threaten the health-care system. 

The government is also looking at revoking the medical license of two members of the Korean Medical Association, which represents about 13,000 doctors, on suspicion of leading the collective action that could damage the delivery of health care, Yonhap said.

Yoon, who has been driving the plan to increase the number of doctors, has seen a boost in his support rate. This could help his conservative People Power Party as it tries to take control of parliament in April elections.