Activists defy ban on demonstrations in Paris as more than 140 heads of state arrive for UN summit on climate change.

Police have fired tear gas and used pepper spray to disperse a group of anti-global warming activists who marched in Paris in defiance of a recent ban on public demonstrations, a day before the start of a key UN summit on climate change in France’s capital.

The tough response by riot police came on Sunday after a group of mostly masked protesters took to the streets to call on world leaders to take action towards curbing man-made emissions.

On Monday, more than 140 heads of state will converge in Paris to broker a deal to limit emissions.

Earlier in the day, in a bid to circumvent security measures implemented after the November 13 attacks claimed by ISIL that took 130 lives, thousands of shoes were placed in the city’s sprawling central plaza to represent citizens urging a climate agreement.

Organisers of the display said that the Vatican donated a pair of shoes bearing the name of Pope Francis.

Hundreds of people also formed human chains in the late morning, interlinking arms and hands along the sidewalks between the central Place de la Republique and the Bataclan concert hall, where nearly 100 people were killed in one of the attacks.

Thousands of shoes were placed in the city’s sprawling central plaza to represent citizens urging a climate agreement [Reuters]

“Together with the hundreds of thousands who will take to the streets around the world this weekend, the pope is sending a powerful signal that leaders arriving for the Paris summit simply must not ignore,” organiser Emma Ruby-Sachs said in a statement.

Four faith organisations turned over a petition on Saturday bearing 1.8 million signatures calling for leaders to adopt a fair deal that would also help poorer countries adapt to a changing climate.

Environmental organisation Greenpeace also floated a hot air balloon that said, “rise up for renewables”.

The Eiffel Tower planned a projection of artist statements for climate solutions.

Related: Can World leaders reach climate change deal?

The coalition of climate organisations said that hundreds of thousands of people would take part in 2,000 events in 150 countries.

“There couldn’t be a more important time to work for climate justice, and the peace it can help bring,” Haeringer said.

In Australia, more than 45,000 people marched through the streets of Sydney on the eve of the climate summit.

Earlier in the weekend, more than 50,000 had marched and rallied at events in Melbourne, Brisbane, Canberra and elsewhere.

On a smoggy Sunday morning in India, more than 5,000 residents of New Delhi participated in a meditation session and listened to musicians sing songs dedicated to the earth as part of events to highlight the need for an agreement at the climate summit.

Police in Berlin said they were expecting 15,000 people to take part in the Global Climate March in the German capital.

Beginning on Monday, representatives of nearly 200 countries will gather in Paris to make the final push for a new climate agreement that will include carbon emission reductions by developing countries for the first time.

Related: Cambodia’s ‘beating heart’ and climate change disaster

The goal of the agreement is to stop the global temperature from rising more than two degrees Celsius over pre-industrial times, and thereby avoiding catastrophic loss of human life from rising sea levels and severe weather.

Earth’s temperature is currently on course to rise at least four degrees this century as a result of increasing amounts of carbon dioxide and other greenhouse gasses in the atmosphere.