"You say it best when you say nothing at all," Instagram user Gweezilla commented on Keating's post, referring to his hit song made famous by the romantic comedy film Notting Hill.
Keating, who shot to prominence in the 1990s as a member of boyband Boyzone, posted a photograph of about two dozen ships anchored off the city on Instagram and Twitter, with a caption that said the traffic was related to the coronavirus.
The city-state's Maritime and Port Authority (MPA) also responded to Keating's post on Monday, saying a ship arrives or leaves Singapore every 2-3 minutes and that there can be about 1000 ships there at any one time.
"#WeCouldntSayNothingAtAll," the MPA added.
Keating's posts were not available on Tuesday.
The singer on Saturday performed at an event in Jakarta, Indonesia, but it was not immediately clear if he was in Singapore.
Singapore has had just over 100 cases of the coronavirus.