Japan's prime minister says the U.S. bank bailout is "insufficient" and contributing to the renewed plunge in global stock markets.

Prime Minister Taro Aso told parliament Thursday that that "since (the bailout) was insufficient, the market is again falling sharply."

Japan's key stock index plunged more than 10 percent in morning trading following another big sell-off on Wall Street Wednesday on fears that the world is entering a recession.

The U.S. Congress earlier this month approved a plan to use $700 billion of public money to buy bad mortgage-related securities and loans from troubled financial institutions. Some $250 billion of that will be used to buy shares in leading U.S. banks.