The World Wildlife Fund is trying to block proposed oil exploration in Africa's oldest national park where 200 gorillas live.
The Swiss-based conservation group filed its complaint Monday with Britain's Department for Business Innovation and Skills in a bid to stop SOCO International's exploration in Congo's Virunga National Park, a World Heritage site listed by UNESCO as being "in danger".
The WWF says SOCO's plan violates Organisation for Economic Cooperation and Development guidelines on sustainable development, public disclosure and other points.
The Department for Business Innovation and Skills is the arm of the British government responsible for overseeing compliance with OECD guidelines.
Last year the Congo government authorised SOCO, which is based in London, to explore the region, saying that economic interests take precedence over environmental considerations.