SEOUL (BLOOMBERG) - After at least four people drowned in basement homes during the worst storm to lash Seoul in more than a century, South Korea's capital city is planning to phase out such dwellings that came to symbolise yawning inequality in the Oscar-winning film Parasite.

Seoul is considering banning construction of underground and semi-underground houses after coordination with the government, according to a statement on Wednesday (Aug 10).

Landlords will be given 10 to 20 years to remove such structures known as "banjiha" homes from existing buildings. As of 2020, about 5 per cent or 200,000 homes in the city were basement or half-basement flats, according to the Seoul Metropolitan Government.

The announcement came after the worst rainstorm in 115 years dumped 525 millimeters of rain in parts of Seoul earlier this week and killed at least 11 people.

Among them were three family members - a woman in her 40s, her sister and the sibling's teenage daughter - who were found dead after being trapped in a submerged semi-basement home in Sillim-dong, not far from the affluent Gangnam area.

Another woman in her 50s who lived in a similar residence also drowned, according to DongA Ilbo newspaper.

The central characters of Parasite, the Korean-language film that won the Oscar for best picture in 2020, are portrayed as those living in such basement houses, struggling to make ends meet, largely out of sight and ignored by the wealthy.

Inequality in South Korea, Asia's fourth-biggest economy, has worsened in recent years, especially after the coronavirus pandemic.

The income gap between the top 20-percent of households and the bottom-most group has widened since 2019, a report released by Shinhan Bank showed in April.