Climate activist Greta Thunberg said that adults should stop making young people “angry” over global warming.
Ms Thunberg was speaking after her arrival in Lisbon, Portugal, after a two-weeks-plus journey across the Atlantic from her starting point in Virginia, US.
“People are underestimating the force of angry kids,” she told reporters.
The 16-year-old is on her way to the COP25 climate summit in Madrid.
She is taking a stand on more polluting forms of transport by sailing, rather than flying or travelling in cars.
Responding to a question from a journalist who said some adults viewed her as “angry”, Ms Thunberg said: “We are angry, we are frustrated and it’s because of good reasons.
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“If they want us to stop being angry, maybe they should stop making us angry.”
She had originally planned to travel from the US to a UN climate summit in Chile.
But the South American nation had to give up the event due to civil unrest.
The venue changed to Spain, and so Ms Thunberg hitched a ride on a 48ft sailing catamaran called La Vagabonde.
She travelled with Australian YouTubers Riley Whitlum and Elayna Carausu, as well as Briton Nikki Henderson – who is a professional yachtswoman.
Their boat uses solar panels and hydro-generators for power.
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