New Australia PM defends Kiwi crackdown on maiden trip

Australian Prime Minister Malcolm Turnbull faced a grilling about his country's harsh immigration policies Saturday while visiting New Zealand on his first overseas trip since seizing power.

Turnbull, who ousted Liberal predecessor Tony Abbott in a party-room coup last month, would normally expect a warm reception in New Zealand, Canberra's closest ally.

But there is anger on the other side of the Tasman Sea at the treatment of Australian-based New Zealanders caught up in a crackdown on migrants with criminal convictions.

Tightened rules allowing deportation of foreign nationals who have served 12 months or more in an Australian jail have left hundreds of Kiwis facing an enforced return to New Zealand.

With 650,000 New Zealanders living in Australia, Turnbull's counterpart John Key has raised concerns the numbers could rise steeply and that many people were being unfairly targeted.

New Zealand media have highlighted numerous cases where people who moved to Australia as toddlers were being deported over convictions for relatively minor crimes such as shoplifting.

Some have been arrested in dawn raids and locked up in migration detention centres, including one at remote Christmas Island in the Indian Ocean.

The issue dominated talks between the leaders in Auckland on Saturday, with Key describing the discussion as "frank, honest and constructive".

He said he urged Turnbull to consider the plight of New Zealanders facing deportation who were not high risk and had long-term ties to Australia.

"I think in the spirit of mateship there should be some compassion shown," he said.

While Turnbull said he was "empathetic", he insisted Australian law applied equally to all foreign nationals and no special exemption could be made.

But he said New Zealanders in detention centres had the option of returning to their home country while their appeals were being processed, rather than remaining locked up.

He also promised more resources to speed up the appeal process, while arguing the high number of New Zealanders caught in the dragnet was due to the policy being relatively new, meaning a backlog of cases.

"Those numbers will decline and settle at a relatively low number going forward," he said.