None of the world’s challenges loom as large as climate change, the United Nations chief told a major climate action summit on Tuesday, reiterating his belief that global warming poses an “existential threat” to humanity.

In 2017, solar energy dominated global investment in new power generation like never before, according to a new United Nations-backed report, which shows a steady move away from fossil fuel-based power production to ‘green’ power sources.

Taking a stand against ongoing threats, harassment and murder of environmental defenders, the United Nations on Tuesday launched an initiative enlisting business communities to champion a clean and healthy environment.

Big cats, the planet’s most majestic predators, are under increasing threat – mostly caused by human activities – and this year’s World Wildlife Day, the United Nations is joining the world in raising awareness to their plight and galvanizing support for the many actions already under way to save these iconic species.