According to the Heritage Foundation, a conservative American think tank, oil production from Angola has increased so significantly that Angola now is China's biggest supplier of oil. "China has extended three multibillion dollar lines of credit to the Angolan government; two loans of $2 billion from China Exim Bank, one in 2004, the second in 2007, as well as one loan in 2005 of $2.9 billion from China International Fund Ltd."