In August protesters held up some stolen portraits of Emmanuel Macron in France

Eight activists went on trial in Paris on Wednesday for stealing official portraits of French President Emmanuel Macron from public buildings as part of a protest over climate change.

The activists, aged 23 to 36, have been charged with theft after taking down the pictures from local government offices around the capital in February.

The acts of civil disobedience were part of a movement called "Take Down Macron" which was intended to highlight alleged inaction by the French government over global warming.

The group behind it, Non-Violent Action COP21 (ANV-COP21), claims that 128 portraits have been stolen across France, while 57 people face "group theft" charges which carry a maximum five-year jail term.

"We came to a point when he had tried everything," Felix Veve, one of the defendants, told AFP outside the court in northwest Paris on Wednesday where several hundred supporters held up banners and signs in support.

"We'd marched, we'd organised petitions, we'd tried to convince as many people as possible. The government doesn't listen. Emmanuel Macron is deaf to our calls," Veve said.

At the end of August, several hundred protesters held up some of the stolen portraits during a protest in southwestern France near Biarritz where Macron was hosting a G7 summit of world leaders.

The 41-year-old French leader said recently that he had "changed very profoundly" in his attitude to climate change and has promised to put the issue at the heart of the second half of his presidency.

"The mobilisation by young people for several weeks and months, that is still going on, has made me think about things," he told the Konbini website on August 23.

Macron pushed fellow leaders from rich countries at the G7 to increase their commitments in cut carbon emissions, and he is also supporting global efforts to combat harmful HFC gases, which are used in air conditioning and fridges.

Analysts say his new focus on environmental issues is partly due to public pressure and partly for domestic electoral reasons, with the Greens making strong gains in the European Parliament elections last May.

'Symbolic action'

The theft of the portraits fits a pattern across Europe of increasingly radical protests by campaigners to highlight the risks of climate change, with the group Extinction Rebellion at the forefront.

In July, French police were filmed spraying tear gas in the faces of protesters at point-blank range as they blocked a bridge in the centre of Paris.

"Solidarity with the people who took down the portraits of our presidential monarch," leftwing leader Jean-Luc Melenchon wrote on Twitter on Tuesday.

The head of campaign group Oxfam in France, Cecile Duflot, also backed the protesters, writing: "It's a symbolic action and not a group theft."

All public schools and government offices display the president's portrait, with Macron's showing him perched on the edge of his desk with two mobile phones and the memoirs of French resistance hero and post-war president Charles de Gaulle behind him.

It is not the first time Macron's picture has been targeted.

In October 2017, mayors in the central Creuse region turned his picture around so that Macron faced the wall, to protest cuts to local government budgets and job losses.

The first trial over the thefts of presidential portraits took place at the end of May in the eastern town of Bourg-en-Bresse.

An environmental campaigner was fined 250 euros ($275) and five others received suspended fines.