Health Minister Ong Ye Kung said on Tuesday (Sept 21) that the Government is monitoring hospital capacity closely and may have to impose more restrictions if the Covid-19 situation worsens.
Singapore already has a suite of measures in place, and to go further would be a "last resort", he added in Mandarin in an interview with Lianhe Zaobao.
Mr Ong said: "We had planned to have a preparatory period, during which we can gradually open up while handling perhaps 100 to 200 cases a day. But Delta did not wait for us to be ready and attacked us first."
"The fight against Delta is really like a war... and it can spring surprises which you never expected, so you have to be able to adapt and change strategies quickly."
He added that two factors are crucial in deciding if Singapore has reached a critical stage - the number of serious cases and hospital capacity.
And the Government has been keeping a close watch on both indicators to ensure that intensive care units and the healthcare system in general are not overwhelmed.
Asked about his assessment of the current situation, Mr Ong said that as of last week, things were still under control. But he added that the situation changes daily.
He also noted that a new balance had to be struck with the virus, and people would have to learn how to co-exist with Covid-19.
At the current stage of the pandemic, it is no longer possible, and also futile, to go into protracted lockdowns, he said, noting that infection numbers will inevitably go up again once lockdowns are lifted.