In this Thursday, Feb. 21, 2019 file photo, Swedish climate activist Greta Thunberg, center, holds a sign which reads: 'school strike for the climate' during a climate march in Brussels. Germany's foreign minister Heiko Maas says that about one year after Thunberg first staged a protest in front of the Swedish parliament he's "grateful" for her climate protests. (AP Photo/Geert Vanden Wijngaert)
Foto: Geert Vanden Wijngaert