The doctors' protest against the South Korean government's planned medical enrollment quota hike is taking a toll on medical school campuses as students are boycotting classes en masse.

All 40 medical schools in the country have either postponed the opening of classes or are unable to hold lectures, as students refuse to attend classes, according to the Education Ministry.

"Ten medical schools have been confirmed to be boycotting classes," the Ministry of Education remarked. "To put it another way, out of the 40 medical schools nationwide, 10 have opened, while the remaining 30 have adjusted their academic schedules (postponed classes)."

Once students fail to meet minimum attendance requirements, they could face academic probation, raising the possibility of a large-scale "collective furlough" of medical students, which could also lead to a medical student shortage.

Usually, universities fail students for missing more than one-third or one-fourth of a class in a semester. Medical school requires students to take another year of studying for failing even one class. In the case of Hallym University, students have continued boycotting classes though their semester started last month, hinting at possible collective furloughs if they fail to return by Thursday this week.

Schools that have postponed lectures also have no choice but to open by the end of April, as the education law stipulates that a course of a single semester has at least 15 weeks of classes.

The government has offered to talk to medical students and said it will discuss normalizing academic operations if they respond, assuring the public that Thursday will not be Maginot's line for a collective flunk.

Some 18,800 students, or 30 percent of the total medical school students in the country, have handed in their leave of absence applications, of which 5,500 were registered through valid procedures. However, the Education Ministry maintains a firm stance that "collective action cannot be the reason for absence," denying the validity of many absence registrations.

Meanwhile, the health ministry sent prior notices of license suspension to some 5,000 trainee doctors who have defied the order to return to work on Monday. The doctors will be required to submit their opinions on punitive measures by March 25.

With the government vowing to take legal action against junior doctors making threats to their colleagues, or impeding their return to hospitals, the ministry will open a hotline Tuesday to protect physicians wishing to return.

Health authorities also pledged to take lenient measures if trainee doctors return to work before administrative procedures to suspend their licenses are completed.