Billie Eilish, Lenny Kravitz and Jon Batiste are headlining a concert aimed at building awareness around climate at the foot of the Eiffel Tower in Paris on Thursday.
The concert, organised by NGO Global Citizen, features on the sidelines of an international summit launched by President Emmanuel Macron.
Artists H.E.R. and Eilish's brother Finneas are also on the bill for the free show at the Champ de Mars below the Parisian landmark.
The venue hosted a previous Global Citizen concert in 2021 with Elton John and other huge stars that also had parallel concerts in several cities around the world.
Eilish, 21 and a seven-time Grammy winner, is known for her environmental advocacy.
She has given up the use of private jets and during her 2022 "Happier Than Ever" tour, she set up "eco villages" to encourage recycling, voter-registration and provide information on environmental groups.
Thursday's concert, titled "Power our Planet: Live in Paris", seeks to build pressure for a "new global financial pact".
It wants rich countries to keep promises for climate-related funding to poorer nations, reform development banks to focus on the environment, and get commitments from large polluting companies to move towards net-zero emissions.
"Crises are multiplying and the number of those who place their hope in peace and multilateralism will only grow if we, as a global community, demonstrate that we are there to help the most vulnerable," Macron said in a statement.
The stars will perform a series of short sets for around 20,000 spectators who won a lottery for free tickets.
It will also be broadcast online via multiple sites.
Actresses including Oscar-winner Michelle Yeoh will also be present to speak during the event.