Major ratings agency Moody's Investors Service downgraded Japan's sovereign debt rating by one notch Wednesday, putting fresh pressure on the country's political leaders to repair its finances. Moody's said it was cutting Japan's government bond rating to Aa3 from Aa2, citing the "large budget deficits and the build-up in Japanese government debt since the 2009 global recession", according to Dow Jones Newswires. It is the first time since the March 11 earthquake and tsunami that a major ratings agency downgraded Japan's sovereign debt. Moody's said the outlook was stable. The action puts Moody's on a par with other major ratings companies Standard & Poor's and Fitch Ratings, both of which rate Japan's sovereign debt at AA- with a negative outlook. Moody's last changed Japan's rating in May 2009, when it raised it from Aa3. As Japan's fiscal position worsened this year, it lowered the outlook to negative on February 22. It announced a review for possible downgrade on May 31, voicing doubt the country's leaders would be able to contain the industrialised world's biggest debt. The downgrade comes less than a week before Japan is to select a new prime minister to become the nation's sixth leader in five years. Japan's debt stands at around 200 percent of its GDP, after years of pump-priming measures by governments trying in vain to arrest the economy's long decline. A rapidly ageing population, entrenched deflation and a feeble economy have made it hard for lawmakers to curb borrowing. Japan is set to issue more bonds later this year to help finance reconstruction from the March disaster