Germany and China have expressed concerns over US plans to pump 600 billion dollars into the US economy. German Finance Minister Wolfgang Schaeuble said the US would not solve its problems, but create extra problems for the world instead. He said it is not that the Americans have not pumped enough liquidity into the market, but now to say let them pump more into the market, is not going to solve their problems. Meanwhile, China's Central Bank head Zhou Xiaochuan urged to look into reforming the international currency system. He said if the domestic policy is optimal policy for the United States alone, but at the same time it is not an optimal policy for the world, it may bring a lot of negative impact to the world. The US central bank announced on Wednesday that it would spend 600 billion dollars to buy government bonds, in the hope that the cash injection can kick start the country's economy.