The dollar held close to a six-month peak as jitters over China and global growth weighed on risk appetite, while the yen strengthened as Japan's top currency diplomat sent a warning about the currency after it earlier dropped to a 10-month low.
The dollar eased from a 12-week peak on Monday as traders weighed the US monetary path after Fed Chair Jerome Powell left open the possibility of further interest rate increases, while the yen hovered close to its lowest in over nine months.
The dollar was on the defensive on Monday after a mixed US jobs report provided little directional conviction and as market focus turned to inflation data from the world's two largest economies due this week.
The dollar struggled to make headway on Wednesday after a cut on the US government's top credit rating by Fitch raised questions about the country's fiscal outlook, though it drew some support from a relatively resilient run of economic data.
The end of the dominance of the US dollar is nigh as the Chinese yuan rises and the rest of the world sees the peril of the West's failed attempt to bring Russia to its knees over Ukraine, one of Moscow's most powerful bankers told Reuters.
The dollar is up 2.5 per cent from its recent low against a basket of currencies and stands near its highest level since March.
If investors agree on one thing this year, it's that the dollar is going to fall. That's made the greenback's 2 per cent bounce over the last month particularly confusing.
The dollar rebounded on Monday and hit a one-month high against the yen, as resilience in core US retail sales and impressive Wall Street bank earnings raised market expectations for an interest rate hike from the US Federal Reserve in May.
The US dollar will weaken against most major currencies this year as the interest rate gap with its peers stops widening, putting the currency on the defensive after a multi-year run, according to a Reuters poll of foreign exchange strategists.