When Russian President Vladimir Putin began consolidating power in the early to mid-2000s, he also consolidated his country's energy sector . Putin oversaw the creation of two mega-energy firms — Rosneft for oil and Gazprom for natural gas — as well as a handful of regional firms. And since their inception, Rosneft and Gazprom have been the Kremlin's crown jewels, making up about half of the Russian government's budget and 25 percent of the country's gross domestic product (GDP) during years of high energy prices. Rosneft and Gazprom remain Russia's most strategic assets, even as revenues have declined following the fall of oil prices in mid-2014. But the shrinking revenue pie has left various Kremlin elites scrambling to secure the biggest slice they can get. And the most aggressive competitor is Rosneft, driven by its ambitious leader, Igor Sechin.