New Zealand's central bank kept interest rates unchanged as expected on Thursday amid the euro zone debt crisis, but pointed to a likely rise in the middle of next year.

The Reserve Bank of New Zealand dropped explicit reference to raising rates contained in previous statements, but the bank said its forecast of forward wholesale rates, taken as an indicator for the cash rate, implied a "gentle" rise in the middle of next year.

The bank said global conditions have deteriorated and could worsen further though the impact on the country has been limited so far.