One World: Together At Home, which was broadcast live on Sunday morning Singapore time (April 19), was held to celebrate healthcare and front-line workers around the world and support the United Nations Foundation's Covid-19 Solidarity Response Fund.

The eight-hour global music event featured more than 110 celebrities from around the world, including singers Lady Gaga, Taylor Swift, John Legend and Elton John.

Hong Kong singers Jacky Cheung and Eason Chan performed as well.

Chan, 45, appeared on the show twice and sang his Cantonese song I Have Nothing and the late John Lennon's Love, while Cheung, 58, sang his English number Touch Of Love.

The performances of both singers have been praised by many netizens, but some were upset that Chan and Cheung were introduced as singers from "China" instead of "Hong Kong".

It has sparked a war of words, with Chinese netizens accusing those calling for the use of "Hong Kong" as supporters of Hong Kong independence, while some used the phrase "Wuhan virus" to provoke the Chinese.

And Lady Gaga faced some backlash for calling World Health Organisation (WHO) chief Tedros Adhanom Ghebreyesus a true "superstar" before the fundraising concert.

Taiwanese netizens have accused the WHO of playing "political games" and siding with China by continuing to exclude the island from the international body even during the current coronavirus pandemic.