Arnold Schwarzenegger was joined by experts and activists at at the Austrian World Summit.
"I call on all my environmentalist friends to move past the old ways and to embrace the new environmentalism based on clean energy growth. I call for change,” Schwarzenegger said.
“Change is never easy, but this is an emergency and this emergency demands action. Lives depend on it."
The Austro-American actor founded the annual Austrian World Summit in 2017, with the aim of discussing and promoting solutions to climate change.
It brings together political and business leaders, climate activists, experts, and organisations from around the world, this year under the theme “We Have the Power”.
Speakers at the opening ceremony pointed to the current geopolitical situation having diverse impacts on people's lives: energy supplies are at risk and inflation rates are soaring.
They said that despite the devastating effects of climate change seen in the last few decades, the climate crisis appears to have taken a backseat in global discussions.
In his speech, Austrian President Alexander Van der Bellen warned of the dangers of disinformation, saying "If we follow the fake news, we all will lose."
United Nations Secretary-General António Guterres addressed the conference via video link, saying disasters and dangers “are already mounting with the poor and marginalised suffering the most”.
“But amidst all this, I urge you to remember one vital fact - limiting the rise in global temperature to 1.5 degrees remains possible. The acceleration agenda also urges all countries to step up their climate action now," he said.
Watch the video above to see more about the Austrian World Summit.