The New Zealand dollar pushed higher against the greenback, euro and yen, as commodity currencies led by the Australian dollar staged a rebound.
Around 8am the kiwi was buying US71.58c, up from US71.16c at 5.30pm yesterday.
Traders said US dollar weakness was partly a function of fading expectations for a US interest rate hike this year.
The euro has rallied more than 5 percent so far this month on easing concern about the euro zone debt crisis and after weak US economic news eroded the greenback's yield appeal.
But after reaching a 10-week high against the US dollar near $US1.3030, the euro fell back as investors took profits ahead of European bank stress test results, with concerns the tests will show some banks need to raise more capital.
BNZ markets strategist Mike Jones said market appetite for the NZ and Australian dollars against the yen helped underpin support for both currencies.
Reserve Bank of Australia minutes yesterday highlighted concerns about the European financial markets as well as expectations for a moderation in inflation, Mr Jones said.
But overall the RBA had a positive outlook on Australia's terms of trade and a more sustainable rate of growth in China and broader Asia.
While the RBA may keep Australian interest rates on hold in August, markets continued to favour further hikes in later months, Mr Jones said.
That sentiment coloured trading yesterday afternoon and overnight.
The NZ dollar rose to 0.5553 euro at 8am from 0.5488 at 5.30pm, and was up to 62.59 yen from 61.94.
Recent yen strength has prompted market investors to consider how Japanese authorities may deal with a firmer currency. Traders suspect they may not want to see the 85-yen level against the US dollar breached, though many doubt Tokyo is ready to intervene.
The kiwi was little changed against the Australian dollar, buying A81.07c at the local open, while the trade weighted index rose to 67.28 at 8am from 66.82 at 5.30pm.