Hundreds of thousands of people have taken to the streets across the globe – from Canberra and Kabul to Cape Town and Berlin – to demand that leaders tackle climate change in the run-up to a UN summit.

Many were children who skipped school to take part in the second Global Climate Strike, following a similar event in March that drew large crowds.

Events kicked off in Australia, where protesters marched in 110 towns and cities, including Sydney and the national capital Canberra.

Demonstrators called for their country, the world’s largest exporter of coal and liquid natural gas, to take more drastic action to reduce greenhouse gas emissions.

Organisers estimate more than 300,000 protesters took to Australian streets in what would be the country’s biggest demonstration since the Iraq War in 2003.

The protests are partly inspired by the activism of Swedish teenager Greta Thunberg, who has staged weekly demonstrations under the heading Fridays for Future over the past year, calling on world leaders to step up their efforts against climate change.

Greta is expected to speak at the UN Climate Action Summit on Monday.

Hundreds of rallies took place across Europe, including in the Czech Republic, Germany, the UK and Poland.

In Berlin, organisers said 80,000 people gathered in front of the capital’s landmark Brandenburg Gate, not far from Chancellor Angela Merkel’s office where the cabinet was thrashing out the final details of a plan to curb Germany’s greenhouse gas emissions.

Smaller protests took place in Asia, including in Japan, South Korea, the Philippines, Hong Kong and India.

In Africa, rallies were held in Johannesburg and the South African capital Pretoria, as well as Kenya’s capital Nairobi.

Experts say Africa is the most vulnerable continent to climate change and the least equipped to deal with it. Governments have pleaded for more support from the international community.

Further rallies are planned later Friday in the US, where organisers say more than 800 events are expected.