"The climate issue is totally connected to the social issue," Keller told Euronews as she kicked-off a series of interviews with those in the running for the EU’s top job.
"It's the poorer people who suffer most from climate changes and its the poorer people who actually have much less CO2 emissions than richer people," she said.
Keller is among those hoping to succeed Jean-Claude Juncker as president of the European Commission after May’s elections.
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There is a host of other candidates also in the running, like Frans Timmermans, currently the EC’s first vice-president, who is nominated by the socialists. We’ll be interviewing him on Friday (April 26), followed by: Violeta Tomic, candidate of the Left (April 30), Guy Verhofstadt, representing the Liberals (May 13) and Jan Zahradil from the Conservatives (May 14).