A police officer outside Downing Street was filmed taking the knee alongside protesters marching in solidarity with Black Lives Matter.
Thousands gathered in Hyde Park on Wednesday before marching on Parliament Square in response to the killing of George Floyd in the US.
Traffic was blocked in certain areas as some climbed on phone boxes and sculptures with megaphones to whip up loud chants of "silence is violence" and "say his name, George Floyd".â€‹
As people marched outside Downing Street, some were filmed asking a police officer to take the knee, something which is fast becoming a global sign of respect and solidarity with the protests.
The Met officer then dropped to kneel on the pavement with the demonstrators.