Protests have taken place around the world calling for action to avert environmental catastrophe.

From London to Sydney, here’s a look at some of the millions of people joining the global youth climate strike.

Climate strike
A ‘polar bear’ joined children from the Terra Nova secondary school in Cheshire to demand action to stop global warming (Peter Byrne/PA)
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A protester at Millbank in London held up a poster of climate activist Greta Thunberg (Gareth Fuller/PA)
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Thousands gathered on the unseasonally hot September day in Victoria Park Gardens to warn against global warming (Jonathan Brady/PA)
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A younger protester needed a lie-down as handmade posters warned of the need to tackle climate change (Gareth Fuller/PA)
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Students at a large protest in Manchester expressed their anger at Donald Trump (Peter Byrne/PA)
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There was a big turn-out at the protest in Cambridge (Joe Giddens/PA)
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Protesters in the city later held a ‘die-in’ to warn about the threat to the planet (Joe Giddens/PA)
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Young and old also took to the streets of Birmingham (Jacob King/PA)
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Protesters in Cullercoats, Tyneside, staged their protest at the seaside (Owen Humphreys/PA)
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Pupils from Colaiste Bride School made their point with striking posters at a protest in Dublin (Brian Lawless/PA)
Philippines Climate Protests
Thousands of miles away in the Philippines, activists displayed their message in front of ‘a human globe’ formation (Bullit Marquez/AP)
South Korea Climate Protests
South Korean protesters held portable LED lamps to show the need for renewable energy (Lee Jin-man/AP)
India Climate Protests
In India, young protesters gathered outside the Ministry of Housing and Urban Affairs in New Delhi (Manish Swarup/AP)
Germany Climate Protests
Activists blocked a road in Frankfurt, Germany, during rush hour (Michael Probst/AP)
Australia Climate Protest
A large inflatable globe was bounced through the crowd as thousands protested in Sydeny (Rick Rycroft/AP)