Karim Masimov, credited with steering Kazakhstan through the global financial crisis, has quit as prime minister of Kazakhstan.
Masimov, Kazakhstan's longest serving prime minister, was a loyalist to President Nursultan Nazarbayev, who appointed him in January 2007, according to Reuters.
A decree published on the presidential website confirmed that Nazarbayev had accepted Masimov's resignation, though the Associated Press noted that the reason was unclear.
Nazarbayev is an all-powerful figure in Kazakhstan and in a recent interview with Reuters, Masimov said more political reforms were needed — including reforms to the justice system.
The Australian Associated Press cited a government source as saying that Masimov's successor would be First Deputy Prime Minister Serik Akhmetov, another ally of Nazarbayev.
Kazakhstan, home to 16.7 million people, is the second-biggest ex-Soviet oil producer after Russia and the largest economy in Central Asia.
Masimov, 47, fluent in several languages, was widely respected among international investors.
He identified "macroeconomic stability" as his number one priority after being re-installed as prime minister in January, Reuters wrote.
More from GlobalPost: Kazakhstan’s Labor Rights Debacle