Actor Sir Mark Rylance has said his decision to resign from the Royal Shakespeare Company over its contract with BP was inspired by teenage climate change activist Greta Thunberg.
Sir Mark quit the company in June in protest over oil industry ties, which were ended on October 2.
He addressed crowds in the drizzling rain at the first day of the two-week long international climate change protests in London.
The actor told the PA news agency: “Greta created a major change in the atmosphere. The particular way she speaks really affected me.
“Individual actions can make a difference.
“Greta Thunberg, a girl who protested instead of going to school, is suddenly known all over the world – she has sparked a huge fire.
“She influenced my decision to resign from the RSC when I did.”
One protester thanked the actor for resigning from the RSC and for “standing up for what you believe in”.
Sir Mark told Extinction Rebellion protesters at St James’ Park: “The collapse of society is certain.
“I have many friends in the entertainment industry who are struggling to come up with stories that match what is actually going on today.
“People have been saying to me, it doesn’t make a difference having a celebrity joining the protests.
“But I want people to know climate change protesters aren’t hippies.
“I am confident these protests are going to lead to a solid change.
“I have seen protests against apartheid, poll tax, and all sorts of things create a change.
“Extinction Rebellion isn’t going to go away.”
Sir Mark, who says he repairs his clothes and drives an electric car, encouraged cheering protesters to stay overnight so police could not remove their gazebos and makeshift wooden signs.