Hundreds of climate change activists shouted "rebellion!" on Monday morning in Amsterdam city and blocked the traffic.
Police have approved plans by activist group Extinction Rebellion to demonstrate on condition they would not block traffic.
The city warned people to avoid the area on the way to work by car or bicycle, because "the police are planning to end the illegal blockade.”
The demonstrators gathered in the main traffic trunk line running through the city in front of the National Memorial Museum. The slogan reads: "Stop talking, start acting" and "tell the truth."