In Pictures: Climate change protest 'The Time is Now' descends on Westminster
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Organisers estimate that 12,000 people - including school children, farmers, grandparents and nature lovers - joined the rally
A coalition of environmental protesters from across the country have descended on Westminster to lobby politicians over the issue.
"The Time is Now" group promised a wide range of people would take to the streets around Parliament, including surfers and nuns, and they would come from a wide range of organisations, such as Christian Aid, the Women's Institute and the National Trust.
Archbishop of Canterbury Lord Rowan Williams, who led a march at the event, said the group had a "vision of the sacredness, depth and solidity of the material world we find ourselves in".
A number of MPs came out of Parliament to talk to the protesters.
Here are some of the pictures from the day of action.
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Protesters gathered on Albert Embankment in London before heading to Parliament
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The event was organised by The Climate Coalition and Greener UK. Shaun Spiers, chief executive of Greener UK, said they wanted to see "an ambitious environment bill and policies that put us on track for net zero emissions by 2045"
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Demonstrators set off their mobile phone alarms en masse to highlight the urgency of the climate issue
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Shadow foreign secretary Emily Thornberry spoke to some of those gathered nearby Parliament
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Tory MP Damian Green talked to one of his constituents
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Lib Dem MP Chuka Umunna attracted a crowd
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Recycling enthusiasts joined members of the Women's Institute, Surfers Against Sewage and Islamic Relief, among a host of other groups
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They want MPs to act now to cut UK carbon emissions and pass ambitious new laws to tackle air and plastic pollution
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