“It’s not over until it’s over,” Moon said during a speech marking his third anniversary of taking office.
“While keeping enhanced alertness till the end, we must never lower our guard regarding epidemic prevention,” he added.
Moon has enjoyed growing public support on the back of his government’s handling of the virus, which led to a landslide victory for his ruling party at last month’s parliamentary elections.
The usually bustling streets of Itaewon were largely empty on Sunday afternoon, with bars and clubs fronting signs reading “Temporarily closed for business” or “Prevention of assembly”.
“I think this incident can happen anywhere, not only in Itaewon,” said Kim Jae-sung, a chef at a neighborhood restaurant.
“What is most important is one’s social distancing, avoiding enclosed places and being aware so that incidents like this won’t happen again,” he told AFP.
Lee Seung-wook, a 22-year-old restaurant worker, added: “We hope customers will be more co-operative when we ask for their names for the visiting records since we all need to work together.”
The country endured one of the worst early outbreaks of the disease outside mainland China, and while it never imposed a compulsory lockdown, strict social distancing had been widely observed since March.
But it appears to have brought its outbreak under control thanks to an extensive “trace, test and treat” program that has drawn widespread praise.
Facilities such as museums and churches have reopened and some professional sports — including baseball and soccer — have started new seasons, while schools are set to re-open starting next week.