The yen rose to its strongest levels in over two weeks against the euro and dollar on Monday, after upbeat Japanese industrial output data prompted investors to cut back their short positions in the currency.
The dollar held near a 3-week low against a basket of currencies after Friday's soft US growth data dampened expectations for an interest rate hike in August.
The focus was on Federal Reserve speakers and a key manufacturing survey due later.
Japanese industrial production rose a stronger-than-expected 1.9 percent in June, supporting expectations that the Bank of Japan will gradually tighten monetary policy after raising rates for the first time in six years earlier this month.
"The industrial output data was robust, and we are getting consistent fears that China may see a modest appreciation of the yuan and the yen is being carried on in the backdrift of that," said Jeremy Stretch, market strategist at Rabobank.
"The dollar is losing some momentum on the basis of the presumption of slower growth ... If we do see a deceleration in the rate of growth but also some slowing in some of the price variables, then that might just perpetuate the current situation of the dollar looking under pressure."
By 1200 GMT, the dollar was down a quarter percent on the day at 114.33 yen, just off a 2-1/2 week low of 114.23 hit earlier in the session.
The yen gained a similar amount against the euro, striking three-week highs at 145.72 yen.
The euro was steady on the day at $1.2752, shrugging off data showing the first estimate of July annual inflation at 2.5 percent, unchanged from June but staying well above the European Central Bank's 2 percent tolerance threshold.
Investors are keen to hear what Fed speakers would say with investors pricing in around 30 percent chance of an interest rate hike to 5.5 percent next week.
San Francisco Fed President Janet Yellen speaks at 1545 GMT on the economy while St Louis Fed governor William Poole is due to speak at 1210 GMT on Chinese growth.
"The surprise would come if she talks up inflation pressures. That could be dollar supportive because you'd have a dovish FOMC member speaking out. I don't think it's likely but it is a risk," said Tony Norfield, head of FX research at ABN Amro.
The Chicago PMI of manufacturing activity, due at 1400 GMT, is expected to drop to 56.0 in July from 56.5 a month earlier.
Earlier this year the yen was heavily sold off, as expectations rose the BOJ would be slow in raising interest rates, making the yen still an attractive funding currency. But analysts say speculators were cutting back on such short positions after IMM data showed they had boosted bets against the yen to record levels in the week ended July 25.
The yen was also supported by lingering speculation that China would allow faster appreciation of the yuan as authorities try to cool the economy's red-hot pace of growth.
The yuan rose to 7.9650 against the dollar on Monday, the highest level since Beijing revalued in July 2005. ABN's Norfield said the yen drew additional support from coupon payments and redemptions on euro zone government debt.