Australian Treasurer Joe Hockey wants to cut taxes to reverse the Aussie drift to New Zealand

Australia has a new fear - a brain drain to New Zealand.

Australian Treasurer Joe Hockey has sounded the alarm, warning that an increasing number of Australian residents are moving to New Zealand, including "high net worth" individuals, The Australian reported on Monday.

Hockey has outlined a proposal to cut taxes to make Australia more competitive.

He told ABC Radio New Zealand's lower income tax rate was "unquestionably" part of the reason increasing numbers of Australian residents were moving to New Zealand.

READ MORE: New Zealanders reversing the brain drain

"New Zealand has a top personal tax rate of 33 cents in the dollar. We have a top personal tax rate of 45 cents in the dollar, plus two per cent for the Medicare levy, plus two per cent for the temporary budget repair levy - so 49 cents in the dollar.

"Sooner or later people start to move to New Zealand and that's what's happening. In fact, in the last 12 months, for the first time in years, there were more people moving to New Zealand than there were New Zealanders moving to Australia."

Lower taxes were part of the attraction.

"The evidence we've seen is some high net worth individuals moving to New Zealand. Yes, we've seen that. But it's not just New Zealand. There are other countries around our region that have lower taxes."

An estimated 500,000 expat Kiwis are believed to be living across the ditch, attracted by better jobs, higher pay and better weather.

As many as 45,000 a year fled New Zealand for Australia some years.

But the exodus slowed to a trickle after the Australian economy slowed down and New Zealand's picked up, along with extra jobs created by the Christchurch rebuild.

In the last 12 months, the number of Kiwis immigrating to Australia was at its lowest since 1991, The Australian reported. The number of people moving to New Zealand from Australia over the same period was 24,300, though about two-thirds of those were Kiwis returning home.