The teenaged activist quoted the beginning of Eighties star Rick Astley's hit "Never Gonna Give You Up" to the crowd, saying: "We are no strangers to love."
She then danced on stage and sang along to the song as the crowd applauded.
Saturday's rendition was not the first time Thunberg has been connected to the song. She posted a tweet as an April Fool joke on April 1, 2021, saying: "I made a video where I talk about some small things we ALL can and should do to stop the climate crisis.We are in this together, and everyone is needed. YOU get to decide what future you’ll live in. So please watch, share and start doing your part today!".
The tweet linked to the music video of the hit song, an internet phenomenon known as 'rickrolling'.