South Korea will reimpose a ban on karaoke bars, nightclubs and some other nightly entertainment facilities as the number of new coronavirus cases surge to three-month highs, raising concerns about a fourth wave of infections.

Chung Sye-kyun, prime minister, on Friday announced the stronger containment measures to be effective in Seoul and Busan, the country’s two biggest cities, for three weeks from Monday. 

The country has been grappling with cluster infections at churches, bars and gyms in the densely populated areas.

The current 10 pm curfews on cafes, restaurants and bars will be maintained while gatherings of more than four people will continue to be banned, he said.

“The fourth wave of virus infections, which we tried to avoid so desperately, seems to be coming closer and getting stronger,” Chung told a daily government meeting on the pandemic.

The tighter measures come as the country’s vaccination drive has hit a snag amid worries over instances of rare blood disorders in people who have had the Oxford/AstraZeneca jabs. Health officials on Wednesday decided to temporarily suspend use of the jabs for people under the age of 60.

Chung told health officials to thoroughly and swiftly review the latest findings by the European Medicines Agency on the safety of the vaccine.

He stressed that the government has secured enough vaccines to inoculate 12m people, nearly one-quarter of its 52m population, in the first half of this year. The country aims to reach herd immunity by November.

The government is expected to announce its decision on the weekend on resuming the use of AstraZeneca’s vaccine for people aged under 60.

Daily new cases hit 671 on Friday, near the highest level since January, increasing the total caseload to 108,269, with 1,764 deaths so far, according to the Korea Disease Control and Prevention Agency.