China has set up a yuan reserve pool along with Indonesia, Malaysia, Hong Kong, Singapore and Chile at the Bank for International Settlements

Putin said Russia was discussing increasing the presence of Chinese cars on the Russian market as well as the opening of Indian supermarket Chains.

While one board member said a weak yen benefitted the economy given the global downturn, others were worried about excessive currency volatility

The dollar index, which measures the currency against the yen, euro and four other peers, was flat at 104.70, below the 105.79 high from Wednesday, a level not seen since late 2002.

Hong Kong Monetary Authority buys HK$12.819 billion ($1.63 billion) from the market during trading hours in New York to stop the currency from breaking its peg to US dollar

The yen has hit 24-year lows - beyond 135 to the dollar - this week and rising bond yields have pressured the Bank of Japan yield curve control

The Bank of Japan ramped up bond buying on Tuesday in a bid to keep the yield on 10-year government bonds at a 0.25% cap, amid renewed pressure from rising global interest rates

The US dollar index scaled a two-decade peak of 105.29 on Monday and held at that level in Asia as the reserve currency gained with yields and as investors seek shelter from the storm

"It is turning into a Black Monday in Asia," Oanda wrote in a client note. "The R-word (is) now on everyone's lips" amid "a scramble to reassess Fed hiking expectations."

Bank of Japan Governor Haruhiko Kuroda said the yen's recent sharp declines are negative for Japan's economy, shifting a long-held stance.

Ministry of Finance, the BOJ and the Financial Services Agency express concern over yen weakness in strongest signal so far that Tokyo may step in to stem the slide

The Japanese yen, which has lost over 14% against the dollar so far this year, slipped to a 20-year low versus the dollar on Thursday