NZ dollar rises against the US overnight

The kiwi dollar rose to 63.39 euro cents overnight. Photo / File

The New Zealand dollar is firmer ahead of Australian inflation data and after the Bank of Japan came out with an open-ended stimulus programme.

The kiwi was at 84.04 US cents at 8am, up from 83.99 cents at 5pm yesterday.

It fell to 74.51 yen, from 75.17 yen at 5.20pm on Tuesday after the Bank of Japan disclosed monetary policy initiatives.

The yen appreciated overnight, turning around a recent trend of weakness.

The kiwi would have fallen more on the yen cross if it had not been firm against the US dollar.

"The Bank of Japan delivered all the things expected but the negative was that they said that the asset purchases don't start to January next year. The timing was a disappointment," Imre Speizer, senior market strategist at Westpac said.

The central bank has been stimulating the Japanese economy by purchasing assets in in dribs and drabs.

"Now they have outlined a timetable and it continues forever until the economy improves - and that is a powerful thing - but we don't get it for another year," Speizer said.

The market is now focused on a core measure of inflation in the December quarter Australian consumers price index report, due out today.

"We are expecting a stronger number than market. Maybe people jumped on that theme," Mr Speizer said.

The market expectation is for the core measure to rise by 0.65 percent in the December quarter.

A strong core inflation number would dampen expectations for a rate cut in Australia in February.

The kiwi was at 79.53 Australian cents at 8am, down from 79.79 cents at 5pm on Tuesday.

It was at 63.09 euro from 62.93, and 52.94 British pence from 52.99.

The trade-weighted index was at 75.41 from 75.34