Alfa-Bank announced on Thursday that its long term credit rating was affirmed by Standard & Poor's at BB+ with a stable outlook.

The bank received a stable rating on Tuesday despite Russia's sovereign rating being revised to negative.

Alfa-Bank's systemic importance level was also raised by S&P to high.

S&P increased Alfa-Bank's probability of needing government support as well, citing increased market shares, a vast client base and the bank's critical role in the Russian payment system.

Alfa-Bank said that it offers a high level of liquidity, capitalization and asset quality. The bank's BB+ rating puts it among Russia's most sustainable banks.

Alfa-Bank is Russia's largest private bank in terms of total assets, customer accounts, total equity and loan portfolio.