National's Simon Bridges says the "war of words" between Australia and New Zealand is at its worst in some time, arguing politicians on both sides of the Tasman are straining relations.
Australian Home Affairs Minister Peter Dutton this week described a planeload of deportees to New Zealand as "trash", putting focus back on Australia's controversial '501' immigration policy.
That allows Australia to send someone back to their home country if they don't pass a character test - such as going to prison for more than 12 months - regardless of whether they still have ties to that nation.
The policy has been called "corrosive" to the New Zealand-Australian relationship by Prime Minister Jacinda Ardern and has been blamed for rising gang activity in Aotearoa. Ardern on Thursday said she will continue to raise the issue with her Australian counterpart.
Dutton's comments have been widely criticised, including by New Zealand Foreign Affairs Minister Nanaia Mahuta, who said they "only serve to trash his own reputation".
But this week's uproar is the latest in a long line of incidents in recent months which has put strain on the New Zealand-Australia relationship.
Bridges, National's Justice spokesperson who briefly held the party's Foreign Affairs portfolio last year, told The AM Show on Friday there is tension.
"The war of words is now as bad it has been in quite some time," he said.
Bridges went on to note Dutton's comments and remarks by Australian Prime Minister Scott Morrison about a trans-Tasman travel bubble being in New Zealand's hands.
"But then on our side, we haven't helped," Bridges said.
He pointed to New Zealand Trade Minister Damien O'Connor suggesting Australia could better its relationship with China by following Aotearoa's lead and showing more respect to the Asian nation.
Those comments were blasted on both sides of the ditch, with Australian government officials said to be "infuriated", a Liberal MP calling O'Connor "unhelpful", and a Wellington expert in international relations saying the minister had stepped in "diplomatic doo-doo".
O'Connor put out a statement saying the Australia-China relationship was a matter for them and phoned his Australian counterpart Dan Tehan, who later expressed respect for the Kiwi.
But, as Bridges also noted, the O'Connor incident came not long after Mahuta raised eyebrows by offering to mediate a truce between feuding Australia and China.
"Even the PM has been a bit head prefect frankly," Bridges said.
But Labour minister David Parker, who appeared alongside Bridges on The AM Show, disagreed with the National MP's assessment.
"I don't find that. My dealings with the Australian ministers, and I have a lot of them, are actually very pleasant."
Ardern said on Thursday that despite the Government's frustration with the 501 immigration policy, our relationship with Australia remains strong.
"There is no breakdown in our relationship at all. We have an excellent relationship with our counterparts in Australia and indeed myself, with PM Morrison, we speak frequently and we work together often. It just so happens on this issue we strongly disagree."
An Australian international relations expert this week examined claims of strain between the trans-Tasman nations, writing that the two countries have long had differences and suggesting that Australia could learn something from New Zealand's way of doing diplomacy.
Among Melissa Conley Tyler's observations was that New Zealand had recently rocketed up a ranking of the world's top soft power nations. Aotearoa now sits at 15, up from 22 - the biggest rise of any nation. Australia is ranked 10th.
Bridges told The AM Show said we shouldn't be thinking that 501 deportees are "angels".
"They have been to prison for sometime, I think in every case. There is not a huge amount of point in whining about it. I think the real question is what David and his Government is going to do about it," he said.
Parker said New Zealand makes its concerns heard.
"We remonstrate with the Australians because we think these people who sometimes left New Zealand at age 2, they have never become Australian citizens. They are Aussies. They are not Aussie citizens, but they have come out of the Australian system which is why we don't think it is fair," he said.
"It goes back to 2014. The Australians are within their sovereign rights to do this. We don't like it, we complain about it, they continue doing it."
Bridges said there are policies New Zealand could introduce that would be "in our interests".
He mentioned another recent example of contention between Australia and New Zealand: the dual-national arrested in Turkey with alleged links to Islamic State, who Australia has stripped citizenship of.
Because of Australia's move, the woman, Suhayra Aden, may be deported to New Zealand. At a fiery media standup in February, Ardern accused Australia of "abdicating its responsibilities" towards Aden.
Bridges said she is "fundamentally an Aussie, but she is coming here".
"We have got a law where we can't even detain her when she gets in. In relation to the 501s, we could have the same reciprocal policies back that way."
But Parker disagreed.
"Tit-for-tat is not the answer here. That is a schoolyard response. It is not what you do in international relations. This is an irritant in our relationship, but they do remain our closest ally and neighbour. I think we have just got to continue making our point," he said.
"I actually don't like the language Peter Dutton used. These are bad people, but really? Taking out the trash? I don't really think that is becoming of a politician. I wouldn't say that, I don't think he should have."
Back in February last year, Bridges was the National Party leader and proposed doing something similar to Australia's 501 policy. Ardern at the time called Bridges "naïve".
"My view is, if we think this policy is wrong, why would we then repeat it?"
Judith Collins, National's current leader, supports a reciprocal policy.