Labour MP Kelvin Davis has headed to Australia to "take up the cause" of Kiwis held in detention centres, but the Prime Minister has labelled his trip a political stunt.
Mr Davis has flown to Sydney to hear the stories of Kiwi detainees waiting to be sent back to New Zealand as well as from advocacy groups.
The issue of Kiwi-born criminals being indiscriminately deported, despite many having few ties to New Zealand, has created some tension in trans-Tasman relations in recent months.
There could be up to 1000 Kiwis affected by the Australian policy which was brought in under former Prime Minister Tony Abbott.
It requires anyone convicted and sentenced to 12 months' prison time or more to be sent back to their country of origin.
There are around 200 Kiwis in detention centres around Australia, a number second only to Iranian visa-holders and asylum seekers.
Of those 200, 40 are being held on Christmas Island.
Labour has been pushing the New Zealand Government on the issue, saying conditions in the centres are "extraordinarily bad".
Mr Davis also believes Auckland Marae should be set up to receive Maori deportees as they reintegrate into society.
But Prime Minister John Key says one MP visiting a detention centre isn't the way to seek change.
"I don’t think a New Zealander wandering along to a detention centre is the way to resolve the issue we've got. I think we should take that up diplomatically, which we're going to with the Prime Minister of Australia over the weekend.
"I'd be pretty sceptical that it's much more than a stunt," he says.
Mr Key is meeting with his new Australian counterpart Malcolm Turnbull tomorrow when he arrives in Auckland for his first overseas trip as Prime Minister.
A bilateral meeting will be held on Saturday and Mr Key says the issue of Kiwi detainees will be on the agenda.
"I think he'll definitely listen and I can definitely give New Zealanders an assurance I'll do everything I can to get what I hope would be a better deal for New Zealanders."
He says anyone with concerns about themselves or their loved ones being held in detention centres have a number of avenues including getting consular support from the Ministry of Foreign Affairs.
He says there is also a review process under the Australian policy.