KIEV, March 11 -- Moody's Investors Service has placed the B1 foreign currency corporate family and debt ratings of NJSC Naftogaz of Ukraine - for which there had been a negative outlook assigned - on review for possible downgrade, Moody's said in a statement.

According to the statement, the rating action follows the decision of Moody's Sovereign Risk Group to place on review for possible downgrade Ukraine's sovereign rating, an action that occurred earlier this month.