Protesters have joined a worldwide wave of marches demanding that leaders craft a pact to avert a climate catastrophe when they gather in Paris for a UN climate summit.

From Australia to New Zealand, the Philippines, Bangladesh and Japan, people rallied at the start of a weekend of popular protests calling for world powers to overcome logjams when the summit opens in the French capital on Monday.

"Protect our common home," declared placards held aloft as thousands gathered in Melbourne on Saturday.

About 150 leaders, including US President Barack Obama, his Chinese counterpart, Xi Jinping, India's Prime Minister Narendra Modi and Russian President Vladimir Putin, will attend the start of the conference, which is tasked with reaching the first truly universal climate pact.

The goal is to limit average global warming to two degrees Celsius, over even less, pre-Industrial Revolution levels by curbing fossil fuel emissions blamed for climate change.

If they fail to do so, scientists warn of a world that will be increasingly inhospitable to human life, with superstorms, drought, and rising sea levels that swamp vast areas of land.

'Destroying nature'

On the eve of Saturday's protests, French President Francois Hollande, host of the November 30-December 11 talks, warned of the obstacles ahead for the 195 nations seeking new limits on heat-trapping gas emissions from 2020.

"Man is the worst enemy of man. We can see it with terrorism," said Hollande, who spoke after leading ceremonies in Paris to mourn the victims of the  November 13 bombing and shooting attacks that shook the French capital.

"But we can say the same when it comes to climate. Human beings are destroying nature, damaging the environment.

"It is therefore for human beings to face up to their responsibilities for the good of future generations."

Potential stumbling blocks in Paris abound, ranging from financing for climate-vulnerable countries to scrutiny of commitments to curb greenhouse gases, and even the legal status of the accord.

The last attempt to forge a global deal - the 2009 Copenhagen summit - foundered upon divisions between rich and poor countries.

French Foreign Minister Laurent Fabius highlighted four key issues still dividing nations, but sounded optimistic that a deal could be reached during the two weeks of talks.

Protest organisers say they expect hundreds of thousands to take to the streets globally this weekend, with further rallies planned in Johannesburg and Edinburgh on Saturday, while similar events were set for Sunday in Seoul, Rio de Janeiro, New York, and Mexico City.

In Paris, French authorities cancelled two demonstrations following the November 13 attacks which killed 130 people at restaurant terraces, a concert hall and the national stadium.

A Filipino woman walks past demonstrators holding banners during the Global Climate March in Quezon City, northeast of Manila, Philippines [EPA]

 
People hold banners during the Global Climate March in Geneva [EPA]
People walk past the art-work 'Where the Tides ebb and flow' by Argentinian artist Pedro Marzorati installed in a pond at the Montsouris park ahead of the COP21 World Climate Summit [Reuters]

Indian school children arrive to present a symbolic globe to the Indian Minister of State for Environment ahead of the COP21 climate change summit in Paris [EPA]

A polar bear-costumed person gestures during 'Earth Parade 2015' in Tokyo [EPA]

Police stand around a climate change protester who had been blocking train tracks in front a train which was supposed to take the German environment minister to the climate summit in Paris [EPA]

Employees put the final touches during the installation of the exhibition 'Paris de L'Avenir,' a showcase for tangible climate solutions in the context of COP21, in front of Paris City Hall [Reuters]

Source: AFP