Greta Thunberg alights from a train to march on COP 25 Madrid

Teenage activist Greta Thunberg pulled in on the overnight train to Madrid on Friday, heading to a gathering of world leaders she says are failing to combat climate change.

In just over a year, Ms Thunberg has inspired younger protesters in a global movement demanding action to slow the atmospheric warming that climate scientists say could ultimately endanger the survival of industrial societies.

Stepping off the night train Lusitania at Chamartin train station in the Spanish capital, the 16-year-old Swede completed a hastily arranged expedition, including a 21-day catamaran voyage across the Atlantic, to a UN conference originally planned in Santiago, Chile.

Ms Thunberg was met by a crowd of reporters but did not speak as she left the train. “I successfully managed to sneak into Madrid this morning! I don’t think anyone saw me ... Anyway it’s great to be in Spain!” Ms Thunberg tweeted after leaving the station.

Thousands of activists from around the globe will simultaneously hit the streets of Madrid and Santiago on Friday to demand urgent action on the climate crisis from world leaders attending the COP25 summit.