Greta Thunberg and hundreds of thousands of her fellow activists took to the streets on Friday to demand more action to curb catastrophic climate change.

Worldwide, there were more than 1,000 demonstrations on Friday as part of an international day of protest organized by the Fridays for Future youth climate movement.

In Stockholm, for example, a number of people took to the streets with leading climate activist Thunberg. Social media footage showed a long protest march through the Swedish capital.

A video shared by Thunberg on social media showed a crowd of predominantly young protesters hopping in unison and chanting, "We are unstoppable! Another world is possible!"

At the front of the crowd, a large banner was held with the words "people not profit," also a hashtag that also represented the day of protest's motto – called by the international climate action movement inspired by Thunberg's weekly school strikes.

Local groups responded to the call with protests around the world, from Britain, to Kenya, New York City, Australia, and South Korea.

The climate activists are demanding a stronger response to climate change, which is already having a devastating effect on many parts of the world.

In response to Russia's invasion of Ukraine, they have also called for less dependency on fossil fuels, such as oil, gas, and coal, of which Russia is a key exporter.

Jul Pehnt, a Fridays for Future spokesperson, said that every day, millions of euros are flowing to Russia and financing the ongoing war on Ukraine.

"One answer to the war must be to phase out all fossil fuels by 2035 at the latest," Pehnt said. "Billions are now needed for the expansion of renewable energies, heat pumps, and public transport."

"The richest capitalist 1%,must be held responsible for their actions and willful ignorance," Fridays for Future said in their description of the March 25 event. "Together, let’s build a system and home where we prioritize #PeopleNotProfit."