Up to 35,000 doctors in South Korea, upset about a law that will hit their pocketbooks, began an indefinite strike on Tuesday, throwing the nation's healthcare system into havoc. The doctors will strike until the government steps in to remedy the situation, a spokesman for the Korean Doctors Association (KMA) said.

But South Korean President Kim Dae-jung said the government would not negotiate ``at the cost of people's lives.''

Hospitals on Tuesday were only treating patients in emergency rooms--before sending them home. Some 250 medical school teachers were mobilised for emergency room duty, at Seoul National University Hospital, its spokesman Ahn Jong-man said.

``First of all, we have to say sorry to the Korean people,'' said Kim Dae-jung, one of dozens of medical interns and residents holding a demonstration at Yonsei University. ``We have to desert our hospitals now, because the government has not replied to doctors' due demands.''

Hospital walls on Monday were plastered with statements recommending patients check out before Tuesday. ``Please don't get sick, don't speed when driving. If you have a car accident or come down with a fever, there will be no doctor to treat you,'' read one such notice.

Doctors are concerned about a change in law that takes effect on July 1 giving pharmacies, instead of physicians, the right to dispense most categories of medicine. That hits the earnings of hospitals and doctors because they have enjoyed substantial margins on the medicines they dispense.

Doctors complain they've been forced to make money prescribing and dispensing medicine because they cannot charge much for examination and consultation under the current system.

``Up until know, hospitals could only make money by dispensing medicines,'' said an internal medicine resident at Seoul Central Hospital. ``Like lawyers, we are entitled to charge fees, but the government has not mentioned that.''

Medical insurance was only introduced in the 1970s. To enlist public support for it, the government set low fees for doctors.

Clinics and hospital have long made up for the loss by selling medicines and through charges for special services.

Said a urologist at Ewha Women's university hospital: ``The government is trying to catch up with advanced countries' medical systems. But the system can't be changed overnight since Korea had a different medical system from the beginning and for sure we are not ready yet.''

On Monday, patients rushed to hospitals to get last-minute treatment and examinations before the strike. People lined up at pharmacies to buy supplies of medicines, fearing a potential breakdown in the medical care system, local pharmacists reported.

The KMA said it expected more than 90 percent of the 18,000 small hospitals and clinics across the country to close in response to the strike call. The government has said it would consider measures to improve the system--but only after it is implemented.

``With the two sides failing to find compromise, the 47 million Koreans are forced to live without doctors for an indefinite period starting today (Tuesday),'' the English-language Korea Herald newspaper said in an editorial.

``We understand that (doctors') demands are valid to some extent. Indeed, medical service charges in Korea have been unrealistically low. ``But this cannot be solved overnight for it is a more fundamental problem related to the history of medical insurance in this country and its weak financial basis.''