Violence and arrests as climate activists protest in UK and France

Activists have stepped up climate protests in Britain and France, with the one in Paris turning violent as windows were broken and barricades set on fire.

A protester walks past a burning barricade during a climate demonstration, in Paris. Source: AP

Environmental activists in Britain and France have stepped up campaigns to get their governments to confront climate change with greater urgency, part of a week of global climate actions.

Thousands of people marched in south Paris to press French President Emmanuel Macron, world leaders at the United Nations and multinational companies to reduce greenhouse emissions faster,

The protest turned violent for a while after dozens of marchers dressed in black broke windows and set fire to makeshift street barricades. Police blocked off side streets and used tear gas and batons indiscriminately to disperse the crowds as demonstrators ran for cover.

Protesters stand in a smoke of teargas during a climate demonstration, in Paris. Source: AP

Around the busy Port of Dover, the English port nearest to France and the main transport link, activists from the Extinction Rebellion group launched a "blockade" to "highlight the vulnerability of the UK's food supply in the face of the ecological and climate emergency".

Ten people were arrested.

Saturday's protests come a day after hundreds of thousands of mostly young people marched, rallied and demonstrated around the world, demanding action to combat climate change.

The Global Climate Strike took place Friday in advance of a United Nations climate summit.

France's Macron will be among those speaking at the UN summit on Monday.

While he has presented himself as a champion of environment issues and stood up to Brazilian President Jair Bolsonaro over the burning Amazon rainforest, climate activists aren't convinced of Mr Macron's sincerity.

On Saturday in Paris, a delegation from Greenpeace pulled a giant float caricaturing Mr Macron as a "King of Blah Blah".

Clement Senechal, a Greenpeace climate campaigner, accused Macron of putting business interests ahead of protecting the environment.

"The statue embodies the approach of Emmanuel Macron regarding the climate issue, which is mainly a smokescreen of fake, false measures," Senechal said. "We are facing climate inaction in France, and we have a big gap between claims and deeds."

Demonstrators raised concerns ranging from ongoing fossil fuel subsidies to deforestation and meat consumption. Dozens of France's anti-government yellow vest protesters joined climate activists to emphasise the link between economic grievances and environmental concerns.

The protest march remained largely peaceful, but troublemakers wearing black who mingled among the marchers broke shop windows, drew graffiti on buildings and set fire to rubbish cans and scooters.

Around Dover in southeast England, the Extinction Rebellion protest disrupted some traffic, but police said the majority of the group's activists stayed within the designated protest area.

The protest was given the go-ahead by local authorities within certain limits, and Extinction Rebellion insisted it would "not cause any disruption to vital supplies" such as medicines.

Police said that there was a brief closure of the A2 highway, one of the main roads into Dover from London after some people obstructed traffic. They said 10 people were arrested on suspicion of public order offences and would remain in custody pending investigations.

Protesters also hung giant banners showing the Extinction Rebellion "XR" emblem from Dover Castle and the town's iconic white cliffs.