The Bank of Japan on Wednesday left its key rate unchanged at between zero and 0.1 percent, and held steady on monetary policy despite increasing concerns over a high yen and the global economy.
In its assessment the BoJ warned Japan's growth was slowing amid uncertainty abroad and market turmoil caused by the eurozone crisis.
Japan's economy "has continued picking up, but at a more moderate pace mainly due to effects of a slowdown in overseas economies," the BoJ said.
It warned: "The sovereign debt problem in Europe could result in weaker growth not only in the European economy but also in the global economy, particularly through its effects on global financial markets."
Japan will "face an adverse effect from the slowdown in overseas economies and the appreciation of the yen as well as from the flooding in Thailand."
The central bank, which expects the world's third-largest economy to eventually return to "a moderate recovery path", added that its policy board voted unanimously to keep its key rate unchanged between zero and 0.1 percent.
Japanese companies have also been heavily impacted after Thailand's worst flooding in decades hit their supply chains and damaged facilities. Toyota and others withdrew earnings forecasts as they assess the scale of disruption.
The disruption comes after companies were near restoring output to normal levels after the March earthquake and tsunami shattered component supply chains. Japanese firms are also grappling with a strong yen that erodes repatriated profits.
The central bank last month announced further easing measures to help safeguard a fragile economic recovery from the impact of a strong yen and a slowing global economy.
In October the bank said it would boost its asset buying programme by 5.0 trillion yen to 55 trillion yen ($713 billion at current rates), with the extra money earmarked for the purchase of Japanese government bonds.
By pouring liquidity into the market, the BoJ hopes to improve flows to help encourage investment and boost business.
It also hopes, by relaxing credit conditions, to put downward pressure on the yen.
"The bank... is steadily implementing the program mainly through the purchase of financial assets," it said in a statement.
Last month the BoJ trimmed its Japan growth forecast for 2011 and 2012 while indicating it would not exit deflation before the end of fiscal 2013.
"The bank has also made it clear that it is committed to continuing the virtually zero interest rate policy until it judges that price stability is in sight," it said Wednesday.