Spain will host U.N. climate change talks in December after Chile withdrew, the United Nations said on Friday, a last-minute switch that raises big logistical challenges and has left activist Greta Thunberg stranded on the wrong side of the Atlantic.

The U.N. climate change talks, known formally as COP25, will be held from Dec. 2 to 13 as originally planned, but in Madrid — over 10,000 km (6,000 miles) away from Santiago.

Chile's government on Wednesday announced it was withdrawing as host of both the December climate summit and the Asia-Pacific Economic Cooperation summit scheduled this month after two weeks of riots over inequality in the South American country left at least 18 people dead.