Two of the world's largest index providers might strip out certain Russian companies from their indexes following the latest round of western sanctions, potentially handing investors another reason to avoid the country.

MSCI late Thursday said it is considering removing VTB Bank's ruble shares from its Russian index after the US Treasury Department slapped the bank with sanctions restricting its access to US financial markets. It cited concerns that if VTB issues new equity, that could possibly lead to some market participants trading the shares in the secondary market, breaking those sanctions.