Up to 50,000 people marched in Paris and other key cities in France to demand action against climate change and to support former environment chief minister Nicolas Hulot who quit over the government's anemic approach to the issue.
When Hulot joined President Emmanuel Macron's cabinet in mid-2017, it boosted France's green image that it earned 18 months earlier when it brokered the Paris Agreement to combat greenhouse gas emissions.
Macron, however, watered down Hulot's initiatives on issues, such as reducing reliance on nuclear energy and banning of the weed killer glyphosate.
Out of frustration, Hulot gave up his post. "Who would be efficient on his own? Where are my troops? Who is behind me?," he said.
Protesters also marched in Marseilles, Strasbourg and Toulouse aside from Paris.
French people took to the streets as they joined a global campaign dubbed "Rise for climate."
Police estimated the protesters at about 18,500, but NGOs put the number far higher at up to 50,000.