Climate activist Greta Thunberg went on trial on Thursday for a public order offence related to a protest outside an oil and gas conference held in London last year.
Thunberg, who became a prominent campaigner worldwide after staging weekly protests in front of the Swedish parliament in 2018, was arrested on October 17.
She and others had been protesting outside a hotel where the Energy Intelligence Forum was hosting oil and gas industry leaders.
The 21-year-old appeared at Westminster Magistrates' Court on Thursday alongside four other defendants, aged between 19 and 59, who have pleaded not guilty to a single offence under the Public Order Act.
The five are accused of failing to comply with a condition imposed by senior police officers to move their protest to designated area near the conference.
Prosecutor Luke Staton said the condition was lawfully imposed as officers reasonably believed the protest "may result in serious disruption to the life of the community".
Thunberg was told she needed to leave or would be arrested by officers, Staton said, adding: "She said that she was staying where she was and so she was arrested."
A smiling Thunberg earlier made her way through photographers and police officers to chants of "climate protest is not a crime" by environmental activists outside the court.
The trial is being conducted by a judge without a jury and is expected to take at least two days. If convicted, the defendants would face a maximum fine of 2,500 pounds ($3,160) each.

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