I hope Mr Ong reconsiders this move.
Without tacit understanding, it will cause a lot of quarrels between Singapore and Taiwan. Imagine a Taiwanese return to Taiwan and get covided, they will blame us. Imagine the alarm that the same Taiwanese will trigger (like this week's cruise) after returning to Taiwan, causing panic in our hotels, restaurants, places of interests?
Bear in mind that he could be covided in Taiwan but both sides will start finger pointing.