Japan's economic minister warns the financial costs of the devastating March 11th earthquake and tsunami, are likely to be worse than first thought. This comes as power shortages curtail factory output and disrupt supply chains in the country.

Meanwhile, the Bank of Japan governor also says the economy is in a severe state. And central bankers are uncertain when efforts to rebuild the tsunami-ravaged northeast will boost growth.

Japan has raised the severity of its nuclear crisis at the Fukushima Daiichi nuclear plant from level 5 to level 7. That's the highest level on the international scale, and on par with the 1986 Chernobyl disaster.

The government estimates material damage alone could top 300 billion U.S. dollars, making it by far the world's costliest natural disaster.