Russia won its first upgrade from S&P Global Ratings since 2006, a milestone decision that returns the world’s biggest energy exporter to investment grade after three years at junk.

The sovereign rating was lifted to BBB- from BB+, with a stable outlook, S&P said in a statement on Friday. That puts it on par with Kazakhstan, Bulgaria and Indonesia. Fitch Ratings, which already has an investment-grade score for Russia, on Friday affirmed the rating at BBB- with a stable outlook.

“The upgrade reflects the track record of prudent policy response that has allowed the Russian economy to adjust to lower commodity prices and international sanctions,” S&P said in the statement.

With the decision, Russia now boasts a non-speculative ranking from two rating companies, potentially triggering inflows of more than $2 billion from funds that track the main emerging-market Eurobond benchmark indexes, according to Societe Generale SA. Moody’s Investors Service, which has Russia one notch below investment grade, set it on course for a possible exit from junk in the next 12 to 18 months by improving its outlook to positive last month.