Thousands of primary, middle school and university students have joined teenage environmental activist Greta Thunberg at a "Fridays for Future" protest in Rome.
Organizers said 25,000 people attended the demonstration in Piazza del Popolo, a square in the centre of Rome.
The protesters chanted "we want Greta" and "with Greta we save the planet" before Thunberg addressed the crowd.
Thunberg told the mass of young people their aim should be that when they are older they can say they did everything they could to help the climate.
"I do many small things just to change my habits, like I have become vegan, I have stopped flying, I have stopped shopping and small things like that," Thunberg said.
"We children are not sacrificing our education and our childhood for the adults and politicians to tell us what they consider is politically possible in the society they have created," the 16-year-old told the crowd. "We have not taken to the streets for them to take selfies with us, and tell us that they really, really admire what we do.
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When asked if she had possibly stolen the limelight away from her cause, Thunberg rejected the notion, saying she did not like being a celebrity.
"I mean I don't enjoy attention, but I enjoy making a difference," she said, adding that she wanted to make sure that climate crisis was always the main focus of any trip.
Thunberg inspired the rounds of protests when she began weekly sit-ins outside Stockholm's Parliament House with her "school strike for climate" sign in August 2018.
The movement sees students skip school on Fridays and instead take to the streets to demand action on climate change.
While the protest in Rome was held on a Friday as usual, Italian schools were already closed for the Easter vacation.
Thunberg admits her hope may be 'very naive'
"I think what I want for the future is just that we fix everything and that we fix the climate and the ecological crisis so that everyone lives in peace, I guess, very naive," she told reporters as she shrugged her shoulders.
Thunberg warned that it was up to current world leaders to find solutions because time was running out.
"When I am grown up, when I am old enough to become a politician, I mean it will be too late to act because we need to act now," she said. "We can't wait for people like me to grow up and become the ones in charge."
Thunberg spoke briefly with Pope Francis in St. Peter's Square on Wednesday. She said Francis, who promotes environmental protection, was "very kind, encouraging" to her.
Students share their concerns
Before Thunberg addressed the crowd in Rome, some of the students attending the protest had the chance to share their views.
The youngest speaker was nine-year-old Alice. "I am 9, nearly 10, and I understand we need to act now. I always loved nature and I don't want it to end, so that's why we are here to save it," she said.
Flavio Frontaloni, a student at the Roma Tre University, drew applause from the crowd after he accused Italian deputy premier Matteo Salvini of rejecting the notion of climate change.
He said Salvini and other members of his far-right League party voted against the Paris Agreement on climate change as members of the European Parliament. "We won't forget this," Frontaloni said.
law/msh (AFP, AP, dpa, Reuters)