TOKYO, Oct 7 (Reuters) - Japan's decision to intervene in currency markets last month reflects tensions in the global currency system, and it is undesirable for this to spark protectionism, World Bank President Robert Zoellick said, according to the Nikkei newspaper
Zoellick will neither support nor criticise Japan's intervention, the Nikkei on Thursday quoted him as saying.
There is no scientific answer for how much China's yuan should rise, Zoellick also said in an interview with the Nikkei.
U.S. currency policy is best left to U.S. officials, he said.
Money flowing to emerging markets from advanced economies in pursuit of higher returns could cause currency appreciation and bubbles, so officials should consider various measures for short-term capital flows, Zoellick said, according to the Nikkei.
The global exchange rate system and rebalancing world economic growth will be an important topic at International Monetary Fund, World Bank and Group of Seven meetings this week. (Reporting by Stanley White; Editing by Joseph Radford)