Japan’s central bank has kept its key interest rate unchanged at virtually zero and extended an emergency loan program for disaster-hit regions.

The Bank of Japan’s nine-member policy board on Friday described the country’s economy as “picking up” after the March 11 earthquake and tsunami that devastated production and exports.

The BoJ also decided to extend by six months a $13 billion loan program for banks operating in the disaster zone. The policy was due to expire at the end of this month.

But the board warned that overseas growth is expected to slow, citing concerns about sovereign debt problems in Europe and the sluggish U.S. economy.