The government says the number of COVID-19 cases could increase again as the falling infection trend has reached its limit.

A senior official at the Central Disease Control Headquarters, Lim Sook-young, said on Tuesday that the decline in infections has slowed recently, with figures expected to hover around the current level for the time being.

She projected a decrease in the country's immunity developed from vaccinations and natural infections, which could lead to another rise in the number of COVID-19 cases.

Lim added, however, that it is too early to determine whether a resurgence is starting now, saying further monitoring is needed on key indices of confirmed cases, critically-ill patients and deaths.

Although the reproduction rate had remained below one for 13 straight weeks, it began to increase from zero-point-74 in the first week of June to reach zero-point-91 last week.