Deputy Health Minister Jun Byung-wang urged intern doctors to "return to the training hospitals within this month."

Unless they do so, Jun said, "Internship training in the first half of this year is impossible", Yonhap news agency reported.

About 12,000 interns and resident doctors have remained off the job since February 20 in protest of the push to hike the number of medical students, forcing surgeries and other public health services to be cancelled or delayed at major hospitals.

In support of junior doctors' labour action, medical professors, who are senior doctors at major university hospitals, have also begun tendering their resignations starting this week.

Prospects for resolving the standoff throughout talks are slim as the government allocated the additional 2,000 medical school admission seats to universities, in a sign that the government won't back down from the plan.

With the mass walkout by trainee doctors continuing for more than five weeks, major general hospitals temporarily shut down part of their wards and rearranged staff.

The five major hospitals -- Asan Medical Center, Samsung Medical Center, Severance Hospital, Seoul National University Hospital and Seoul St. Mary's Hospital -- have suffered more than 1 billion won ($741,344) of losses per day and have been in an emergency management mode to overcome the crisis, according to officials.

Seoul National University Hospital closed 10 out of its 60 wards temporarily, including those for emergency patients and cancer patients after sending patients there to other wards, "for flexible operation given the current situation," an official said.