A senior Labor staffer in Australia has admitted speaking with an acquaintance inside the New Zealand party regarding the rules around New Zealand citizenship.
The latest Government attacks come as New Zealand politicians are trying to downplay the seriousness of the budding diplomatic dispute.
Deputy Prime Minister Barnaby Joyce may have renounced his New Zealand citizenship now and may be ready to just move forward, but the issue will not go away so easily.
Mr Joyce has posted a thank-you message to his supporters on Twitter.
And speaking outside parliament, he says he is committed to staying in the job.
"I came here to do a job. Now I never came here to profess to be a saint or a sinner or anything else. I came here to help, basically, people like them, people who live in those weatherboard homes in little regional towns. That's my job. So I want to focus on that. I don't want to focus on all this other stuff."
But the Government is attacking Labor foreign-affairs spokeswoman Penny Wong after she confirmed her chief of staff asked a friend in the New Zealand Labour Party about it.
He asked questions about New Zealand citizenship laws that pertained to Mr Joyce, and the Government is accusing the trans-Tasman Labor parties of a conspiracy.
The chief of staff's questions ultimately led MP Chris Hipkins to submit queries about citizenship status in New Zealand's parliament.
Barnaby Joyce, the National Party leader, was a New Zealand citizen by descent, it turns out, until Tuesday, when he officially renounced that citizenship.
The Federal Government is rejecting assertions from Labor and from New Zealand government officials that media inquiries actually prompted New Zealand's involvement.
Attorney-General George Brandis tried to move a motion to censure Senator Wong over her admission, but it failed to gather enough support.
Senator Wong says the move was a diversionary tactic.
"This motion by Senator Brandis is a grubby, baseless smear in an attempt ... in an attempt ... in an attempt ... in an attempt to distract attention from this Government's problems. I did not know, nor did my staff member, that the New Zealand Labour Party had placed those questions on notice until this story had broken. He did not know, and neither did I, until Monday. End of story."
Senator Wong says Foreign Minister Julie Bishop is trying to manufacture what she calls a "Kiwis under the bed"* scare campaign.
She says it is out of character with what she terms Ms Bishop's usually capable manner.
Ms Bishop has suggested it would be difficult for the Federal Government to trust the New Zealand Labour Party if it won power in next month's national elections.
The New Zealand party's leader, Jacinda Ardern, has moved to shut down such concern.
"Politics is a constant rock and a hard place.** I'm currently wedged between Ayers Rock and New Zealand. But, ultimately, leadership is about dealing with these issues as they arise. I've dealt with it. This is not going to disrupt our relationship with Australia. And now we have an election to get on with."
New Zealand prime minister Bill English says he, too, is confident in the strength of the trans-Tasman bonds.
Meanwhile, a former Liberal senator has hinted the Federal Government might have known about Mr Joyce's dual citizenship and may have tried to cover it up.
Crossbencher Cory Bernardi has told Sky News the Coalition is taking its accusations against Labor too far.
"And the fact is, if the journalist knew about it, the Labor Party knew about it, how did the Government not know about it? That's the real question: Were they trying to cover something up? So I don't think anything wrong has happened here. I just think the Government has overcooked it."