The yen hit a record low versus the euro and held near 4-1/2 year troughs against the dollar on Monday, staying under pressure after the Bank of Japan chief last week all but ruled out an interest rate rise in July.
Investors' broad hunt for yield was reflected in the Swiss franc - also a relatively low-yielding unit among major currencies - also sliding to fresh record lows against the euro.
The New Zealand dollar stayed firm despite suspected fresh central bank intervention aimed at keeping a lid on the strength of the currency which has surged on the back of the highest interest rates in the industrialised world at 8 percent.
The Reserve Bank of New Zealand entered the market a week ago to knock the kiwi off 22-year peaks versus the US dollar. Risk appetite was supported by gains in global equities. In currency markets this boosted demand for carry trade investments funded by borrowing in low-yielders like the yen and Swiss franc.
"The focus is on the carry trade," said Antje Praefcke, currency strategist at Commerzbank Corporates and Markets in Frankfurt. "With (BOJ Governor Toshihiko) Fukui signalling no rate hikes until consumption is more robust and the SNB saying that rates are neutral, rate differentials will keep the yen and Swiss franc under pressure."
The euro rose to a record high of 165.63 yen, according to Reuters data, before trimming gains to stand at 165.52 yen at 1133 GMT. The yen also hit 15-year lows against sterling, 16-year lows versus the Australian dollar and 20-year troughs versus the New Zealand dollar. The Swiss franc, which has the second lowest interest rates in the G10, hit a record low of 1.6635 per euro on Monday.