Belarus part of the Druzhba oil pipeline system (in russian `Friendship` ; also had been referred as the Comecon Pipeline). Druzhba pipeline system is the world`s longest oil pipeline, it carries oil some 4,000 kilometres (2,500 mi) from southeast Russia to points in Ukraine, Hungary, Poland, and Germany. Today, it is the largest principal artery for the transportation of Russian (and Kazakh) oil across Europe.