Taiwanese diva A-mei was prohibited from singing the song Rainbow at the 2014 Spring Wave Music And Art Festival at Gardens by the Bay on June 7.

This was reported in overseas Chinese media and confirmed by Leap Integrated Marketing Solutions, the marketing and PR consultancy outfit for the event, which was attended by more than 4,000 people.

Reports said the singer was perplexed as she had previously performed the song at her gigs in Singapore, and the lyrics and mood of the song are very gentle.

Rainbow is about gay relationships and the lyrics include "our loves are very similar, we get hurt because of men, yet we continue colliding".

Festival organiser Taiwan's Friendly Dog Entertainment said "official approval was not given". Because Spring Wave was an open event, "there was no way of controlling the ages of those who attend and the song's content was not too suitable", said news.sina.com on Monday.

The report did not say which body or authority blocked the song from being performed.

Film-maker Royston Tan attended the gig and posted on Facebook on Tuesday night: "Singapore can ban A-mei from singing Rainbow but it cannot ban the heart from loving... We're in the international news! How humiliating!"