Moody's Investors Service Inc. said Friday it has lowered its rating on yen-denominated domestic securities issued or guaranteed by the Japanese government to Aa2 from Aa1, given Japan's massive public-sector debt.

The U.S. credit-rating agency also said it maintained a negative outlook on the government rating, but added that Japan's Aa1 foreign currency country ceilings remain unchanged with a stable outlook.

The actions conclude its review for possible downgrades announced in February.