Activists with the Extinction Rebellion movement blocked major roads in Berlin and Amsterdam on Monday at the beginning of what was billed as a wide-ranging series of protests demanding new climate policies.
Founded in Britain last year, the movement, also known as XR, now has chapters in some 50 countries.
In the UK, police have started arresting climate change protesters as they attempt to block roads in central London.
Thousands of people are expected to demonstrate over the next two weeks and witnesses say that their numbers are already overwhelming police in some streets.
Two people have blocked the road outside New Scotland Yard after chaining themselves to a metal cylinder inside a car.
Around 1,000 people blocked the Grosser Stern, a traffic circle in the middle of the German capital’s Tiergarten park dominated by the landmark Victory Column, in a protest that started in the early hours.
Members of Extinction Rebellion have also set up a camp outside Chancellor Angela Merkel’s office, reflecting dissatisfaction with a climate policy package drawn up last month by her government, ahead of what it called an “international rebellion” starting Monday. It says protests are planned in 60 cities worldwide.
In Amsterdam, hundreds of demonstrators blocked a major road outside the Rijksmuseum, one of the city’s most popular tourist draws, and set up tents.