This map shows the main trade routes for oil. It therefore complements the previous map, revealing how oil is diverted in the event of surplus or deficit. It is a global trade, with transportation carried out mainly by ship (tankers). Imports are quite often diversified, with a few exceptions (United States’ dependence on Canada or Europe’s on Russia). The major exporting regions are the Gulf (with Saudi Arabia in the lead), West Africa, Russia, Canada and, to a lesser extent, the northern part of South America.