A South Korean doctor accused of providing drugs to a bar hostess, believed to have blackmailed late actor Lee Sun-kyun, denied the accusations at a court hearing on Tuesday.

The lawyer for the 43-year-old plastic surgeon told Incheon District Court that his client denies all the charges related to the 30-year-old hostess of a high-end bar, who has been charged with receiving the drug from the doctor.

Contrary to what the defendant said, the hostess has already pleaded guilty to all the charges pressed against her.

South Korea's Narcotics Control Act prohibits anyone from giving or carrying banned substances. As the doctor is suspected of providing the drugs to Lee through the hostess and also to her, both of them are subject to legal punishment for the alleged transaction, in addition to other criminal charges they face.

The lawyer did not comment on the other criminal charges against the doctor, saying that they had not yet agreed on their statement.

The next hearing for both defendants will take place on April 18, also at the Incheon District Court.

The doctor is believed to have provided methamphetamine and ketamine -- use of the latter can be punished by drug law if without proper prescription -- to the hostess between December of 2022 and August of last year. The hostess said it was her birthday present.

The hostess is currently under trial for charges including extortion against actor Lee Sun-kyun. Both the hostess and the doctor are also being tried for drug use.

Drug crimes in South Korea can be punished by up to five years in prison under the Narcotics Control Act.

Last year, Incheon police launched an investigation into allegations drug use by Lee, who told police he had taken drugs without knowing what it was. Lee tested negative for drugs, but he was subject to controversy because of the incident, especially after information about his personal life was leaked to local media.

Lee was found dead in his car on Dec. 27.

South Korean police launched an investigation into whether information related to the investigation into Lee was leaked, and confirmed last month that reports had been leaked in some form.

Lee, who was 48 years old, was best-known globally for his role as the wealthy patriarch in Oscar-winning film "Parasite." He had a long career in Korea as a working actor in film and TV dramas spanning over two decades.

He was commemorated during the 96th Academy Awards at the Dolby Theatre in Los Angeles on Sunday. The "In Memoriam" segment paid tribute to those in the entertainment field who passed away last year.