SEOUL, Mar. 25 (Reuters) - Medical professors in South Korea said they will cut back on the hours they spend in practice starting on Monday to support trainee doctors on strike for more than a month over a government plan to boost medical school admissions.

"It is clear that increasing medical school admissions will not only ruin medical school education but cause our country's healthcare system to collapse," Kim Chang-soo, the president of the Medical Professors Association of Korea, told reporters.

He said the professors will start scaling back outpatient treatment to focus on emergency and severely ill patients, while some will submit their resignations.

The strike by the trainee doctors over a plan to increase the number of students admitted each year to medical school from 2025 has forced several hospitals to turn back patients and delay procedures.

The government says the plan is vital to remedy a shortage of doctors in one of the world's fastest-ageing societies, but critics have said the authorities should focus on improving the working conditions of trainee doctors first.

The trainee doctors have been on strike since Feb 20, and President Yoon Suk Yeol, who has made healthcare reforms one of his signature policy initiatives, has vowed not to back down on implementing the admissions plan.

The government has also threatened to suspend the licences of the doctors who have walked off their jobs but on Sunday, Yoon appeared to seek a more conciliatory approach and urged Prime Minister Han Duck-soo to seek "flexible measures" in dealing with the suspension.

Yoon's office said he also ordered the prime minister to form a "constructive consultative body" to speak with all medical professionals.

According to a Gallup poll released on March 15, 38% said the government was doing a good job dealing with backlash from doctors and the medical void amid the doctors' strike while 49% said "not a good job".