Greta: 'People are underestimating the force of angry kids!'

Greta Thunberg has arrived in Portugal ahead of her visit to a big climate meeting.

And she had some strong words for world leaders! She says she wants adults to listen to the voices of young people and to pay more attention to the scientists and climate experts who say more needs to be done to protect the environment.

Later this week she will head to the COP25 climate conference in Madrid. She has just sailed back across the Atlantic to get there after it was moved from South America.

Watch what she has to say and find out more here:

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