Swedish activist Greta Thunberg says young people are "bringing change" to the Madrid climate talks and will not be silenced.
At a news conference Miss Thunberg said that she hoped the negotiations would yield "something concrete"
The 16-year-old was mobbed by press and spectators when she visited the conference centre earlier on Friday.
She had to be escorted away for her own safety amid shouts of "leave her alone" from concerned observers.
Having arrived via overnight train from Lisbon to large crowds waiting for her in Madrid, Miss Thunberg was set to join a large demonstration in favour of rapid climate action this evening.