MOSCOW - Russian President Vladimir Putin on Wednesday took aim at teenage climate activist Greta Thunberg, telling an energy forum he did not share the excitement about her United Nations speech last month.The 16-year-old Swede electrified the UN summit in New York when she denounced world leaders for failing to tackle climate change, unleashing the outrage felt by millions of her peers by demanding: "How dare you?" Putin, chairing a session at an energy forum in Moscow, said: "I may disappoint you but I don't share the common excitement about the speech by Greta Thunberg."No one has explained to Greta that the modern world is complex and different and ... people in Africa or in many Asian countries want to live at the same wealth level as in Sweden."US President Donald Trump mocked Thunberg and Canadian Member of Parliament Maxime Bernier called her alarmist and mentally unstable. Thunberg said their mockery of children showed her message had become "too loud to handle."Putin said young people who paid attention to environmental issues should be supported, adding: "But when someone is using children and teenagers in personal interests, it only deserves to be condemned."I'm sure that Greta is a kind and very sincere girl. But adults must do everything not to bring teenagers and children into some extreme situations."Inspired by Thunberg's solitary weekly protest outside the Swedish parliament a year ago, millions of people have poured onto the streets around the globe to demand governments take emergency action on climate change.Thunberg told the UN conference: "This is all wrong. I shouldn't be up here. I should be back in school on the other side of the ocean yet you all come to us young people for hope. How dare you?."You have stolen my dreams and my childhood with your empty words," she said.Earlier this week, a member of the Russian lower house of parliament, the Duma, invited Thunberg to Russia to deliver a speech.