Greta Thunberg says school strikes have achieved nothing

Activist says 4% greenhouse gas emissions rise since 2015 shows action is insufficient

The global wave of school strikes for the climate over the past year has "achieved nothing" because greenhouse gas emissions have continued to rise, Greta Thunberg has told activists at UN climate talks in Madrid.

Thousands of young people were expected to gather at the UN climate conference and in the streets of the Spanish capital on Friday to protest against the lack of progress in tackling the climate emergency, as officials from more than 190 countries wrangled over the niceties of wording in documents related to the Paris accord.