The chief executive of Kazakhstan’s National Investment Corp., which was set up to help manage the country’s $64 billion oil fund, has been fired, The Wall Street Journal reports.

Berik Otemurat’s departure comes less than a week after he told The Wall Street Journal that he was concerned the oil fund could run out of money within six or seven years as slumping oil prices cut revenue and the government spends its savings.

The 35-year-old executive was replaced by his predecessor, Yeszhan Birtanov, the National Investment Corp. said in a statement. Mr. Birtanov most recently led Kazakhstan’s stock exchange. He previously worked at the central bank and was chief executive of the National Investment Corp. between 2012 and 2014.

“I have to work and think about the strategy,” Mr. Birtanov said in an interview. He said it was too early to disclose any details.

Oil-rich nations from Saudi Arabia to Russia are drawing on their cash reserves as income from energy sales falls. Kazakhstan’s so-called National Fund has shrunk 17% from its peak of $77 billion in 2014. The government is drawing as much as $9.5 billion a year from it for spending. The fund is mostly invested in bonds and had an average annual return of just 1.96% in the last five years.

“We are eating up the National Fund,” Mr. Otemurat said in an interview last week.

National Investment Corp. was set up by the central bank to manage the oil fund but hasn’t actually taken it over. Instead, it is investing $800 million of the central bank’s foreign-exchange reserves. Mr. Otemurat said the government should focus on investing the oil fund in higher-yielding assets such as private equity.

Mr. Otemurat was recruited to the National Investment Corp. in 2014 by then-central bank chief Kairat Kelimbetov, who was fired in November for letting the national currency fall too rapidly after it was allowed to float freely in August.

Photo: yvision.kz