Japan's "A-plus" credit rating is under threat, after Fitch Ratings placed the country's debt on negative watch on Tuesday.
The ratings agency said it could cut Japan's rating in the first half of next year, following the government's decision to delay a consumption tax hike to April 2017 from October 2015.
"The delay implies it will be almost impossible to achieve the government's previously-stated objective of reducing the primary budget deficit to 3.3 percent of GDP by the fiscal year April 2015-March 2016," said Fitch in a report on Tuesday.
Fitch estimates the proportion of Japan's debt to the size of its gross domestic product would reach 241 percent by the end of this year, up from 184 percent at end-2008. The 57 percentage point rise in the ratio would be the second-highest over the period in the A or double-A category after Ireland, the agency noted.