The government will not permit any modified forms of mass rallies in central Seoul on a national holiday early next month, the prime minister said Thursday as the country is bracing for a potential flare-up of COVID-19 cases ahead of the extended traditional holiday.

The remark is seen as directed at "drive-thru" rallies proposed by some main opposition party members as an alternative to the prohibited mass outdoor rallies at Gwanghwamun in central Seoul on the Oct. 3 National Foundation Day.

"(The government) will not tolerate National Foundation Day rallies in Gwanghwamun, including any modified forms," Prime Minister Chung Sye-kyun said during a high-level tripartite meeting involving Cheong Wa Dae, the government and the ruling Democratic Party.

"In accordance with the law, (the government) will sternly take necessary countermeasures (if such mass rallies are held)," the prime minister also warned.

The government has warned of stringent law enforcement against mass rallies in the city center on the day after similar protest rallies on Aug. 15 became a major source of the recent virus resurgence.

The government is also on high alert against a potential growth in transmission cases during the extended five-day weekend that begins Wednesday. It includes the traditional Chuseok fall harvest holiday, which falls on Oct. 1 this year, and National Foundation Day.

"The Chuseok holiday will be a crucial moment for (containing) COVID-19," Chung said, calling on people to refrain from traveling to their hometowns during the period.

During the tripartite meeting, the prime minister also said the government is planning to execute about 70 percent of the fourth COVID-19 response extra budget, worth 7.8 trillion won ($6.7 billion), before the holiday.

The budget bill won approval from lawmakers Tuesday night and the Cabinet the following day.

Separately, a public poll by pollster Realmeter showed Thursday that 7 out of every 10 South Koreans object to the proposed drive-thru protest rallies on National Foundation Day due to transmission concerns.

The poll surveyed 500 South Koreans aged 18 or above Wednesday at the request of radio broadcasting company TBS. (Yonhap)