Greenpeace activists sprayed the road access to the Palais des Nations in Geneva with a black substance on Thursday. The NGO wants oil companies, which it accuses of trying to derail negotiations on plastics, to be banned from the discussions. +Get the most important news from Switzerland in your inbox Around 15 activists from a dozen countries, including Switzerland, took part in the unauthorised action in front of UN headquarters in Geneva on Thursday morning. Some poured water accompanied by iron oxide and other materials, symbolising an oil trail. “Be careful, it's slippery. But it's edible, it's not toxic,” one of them told passers-by who were avoiding the black substance. Signs had also been erected to alert onlookers. Seven activists climbed onto the roof of the security building. The banners they unfurled read “Big oil pollutes indoors” and “The plastics treaty is not for sale”. The perimeter was cordoned off by police, forcing people arriving by car or bicycle to retreat ...