 In early 2010 global mining company Rio Tinto owned 22.4% of Oyu Tolgoi owner Ivanhoe Mines (now Turquoise Hill Resources), and gave both technical assistance and financial support to the project.At the time Rio Tinto had the option of increasing their stake to 46.6%.On 31 March 2010 the Government of Mongolia approved an investment agreement where they would purchase 34% of the project.