Climate activist Greta Thunberg is leading a major protest in Madrid Friday evening, as UN leaders and decision-makers congregate in the Spanish capital for the COP25 UN climate summit.

The COP25 Summit is being billed as a run-up to the COP26 in Scotland next year, when all the countries in the Paris Agreement are expected to state or update their national climate targets.

But Thunberg arrived in Madrid on Friday morning to pressure the decision-makers to take concrete action now. Tens of thousands of protesters are expected to join her on the streets this evening.

Read more: Greta Thunberg heads massive protest in Madrid