Tens of thousands of protesters are set to take to the streets in Glasgow London and other cities in the UK and around the world to demand action on climate change.
In Glasgow, where the crucial UN summit is taking place, about 50,000 people are expected to march through the city centre as part of the Cop26 Coalition's global day of action for climate justice.
Demonstrators will also be on the streets of central London, as well as for 200 events across the UK and around the world, organisers said.
The marches come after thousands of youth activists, including Greta Thunberg and Vanessa Nakate marched through Glasgow on Friday protesting against investment in fossil fuels and failure to tackle the climate crisis.
Ms Thunberg called the Cop26 conference, where countries are meeting in a bid to increase ambition on cutting greenhouse gas emissions, " a global north greenwash festival, a two-week long celebration of business as usual and blah blah blah".
But US special presidential envoy for climate John Kerry has said there is a greater sense of urgency and focus at the Cop26 talks than ever - though he said he was "one of the frustrated" over the pace of climate action and warned that it was "not job done" at the conference.
The latest demonstrations come midway through the Cop26 summit, which has seen about 120 leaders gather in Glasgow to set out the action they are taking and commit to curb deforestation, phase out coal, end funding for fossil fuels abroad and cut methane emissions.
But there is still a significant gap between the measures countries have committed to and what is needed to avoid more than 1.5C of warming, beyond which the worst floods, droughts, storms and rising seas of climate change will be felt.
So countries are under pressure to agree a process to increase ambition in the next decade, as well as deliver finance for developing countries to cope with the crisis and finalise the last parts of how the global Paris Agreement on climate change will work.
As the protests take place, negotiations continue at Cop26, while the conference is also focusing on the role of nature, land use and agriculture in tackling climate change on Saturday.
One of the protesters taking part in Saturday's demonstrations, Mikaela Loach, is a young Scottish climate activist who is challenging the UK's North Sea oil and gas expansion in court.
She said: "Many thousands of us are marching right across the world today to demand immediate and serious action.
"We're clear that warm words are not good enough - and that the next week of talks must see a serious ramping up of concrete plans."
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