'We've been striking for over a year and nothing has happened'
Greta Thunberg has been criticising world leaders at of COP25, a big United Nations climate conference in Madrid, for their lack of action on climate change.
The 16-year-old Greta had previously become stranded in the United States after the location of the conference was unexpectedly changed from Chile to Spain at the last minute.
She arrived at the COP25 event yesterday after spending almost three weeks at sea on a solar powered boat.
She told the conference that "the climate crisis is still being ignored by those in power", and that children having skip school to try and get politicians to pay attention is "not a sustainable solution".