Prince Harry was surprised that the audience "went crazy" for him after he appeared at Vax Live.

Vax Live, a charity event with musicians, celebrities and world leaders, aims to aid the international COVID-19 vaccination rollout.

"Tonight is a celebration of each of you here, the vaccinated frontline workers in the audience and the millions of frontline heroes around the world," he said.

"You spent the last year battling courageously and selflessly to protect us all. You served and sacrificed, put yourselves in harm's way, and acted with bravery, knowing the costs. We owe you an incredible debt of gratitude. Thank you."

Prince Harry and Duchess Meghan are campaign chairs of the Vax Live event, which has been organised by the anti-poverty group Global Citizen.

Other celebrities that appeared include Selena Gomez, Jennifer Lopez and the Foo Fighters.

"Audience went CRAZY for new Cali resident Prince Harry," The Playlist's Gregory Ellwood wrote on Twitter, alongside a clip of the duke on stage.

"Price Harry is back," he continued, sharing another short video of Harry.

"Warns that this portion might be a bit dry. He talks about how global misinformation is a pandemic crisis. Misinformation is effecting everyone and lives could be saved."

@lapublichealth’s Barbara Ferrer #VaxLive pic.twitter.com/q2KxASPXr1

— Gregory Ellwood - The Playlist 🎬 (@TheGregoryE) May 3, 2021

Vax Live is calling on governments to commit to vaccine equity by donating doses and resources.

Despite one billion doses of COVID-19 vaccines being distributed worldwide, there are massive differences between countries in the way they're administered, especially in low socio-economic countries.

"We will all benefit, we will all be safer, when everyone, everywhere has equal access to the vaccine," Harry and Meghan said in a statement.

"We must pursue equitable vaccine distribution and, in that, restore faith in our common humanity. The mission couldn't be more critical or important."