Russian President Dmitry Medvedev speaks during a ceremony marking the start of construction of the Nord Stream pipeline, near the Russian town of Vyborg April 9, 2010. Work will begin on Friday on Nord Stream, Russia's biggest post-Soviet gas pipeline, and its builder said on Thursday alternative fuels, such as shale or liquefied gas, cannot undermine Russia's leading role in Europe. REUTERS/Alexander Demianchuk (RUSSIA - Tags: POLITICS ENERGY BUSINESS)