Some of the biggest investors in the 2014 Sochi Winter Olympics "are requesting financial help from the government to help ease the burden" from the Games' estimated $50B price tag, according to Thomas Grove of REUTERS. In a letter addressed to Deputy PM Dmitry Kozak, who is responsible for the 2014 Games, four major companies listed measures they want adopted to help them "secure a minimum return on investment." The letter "was signed by tycoons" Vladimir Potanin and Oleg Deripaska as well as the heads of Russia's largest bank, state-controlled Sberbank, and state-controlled natural gas export monopoly Gazprom. It cited "a series of problems that were revealed during implementation of the projects that not only made construction more costly but also created hindrances to the future effective use of the venues." Among the problems it named were "the high costs of building in a mountain area with poor infrastructure, uncertainty about the commercial viability of the venues after the Games and the risk of losses after favourable rental rates end in 2015" (REUTERS, 4/2).