In an embarassing legal bungle, New Zealand's response to Melbourne's COVID-19 outbreak has looped in Australian Prime Minister Scott Morrison ahead of his visit.
Mr Morrison is scheduled to visit Queenstown this weekend for the annual Australia-New Zealand leaders' meeting, alongside Jacinda Ardern.
The two governments want Mr Morrison's trip to go ahead, and they will either clarify or fix the law to ensure the visit takes place.
But on Thursday, the NZ Director of Health issued a legal order that casts doubt over Mr Morrison's eligibility to enter or travel around New Zealand.
The directive asks anyone who was in Melbourne between May 20 and May 25 to isolate and be tested.
That timespan takes in Mr Morrison's last visit to the Victorian capital.
The Liberal leader visited Aquaterro, a business in Melbourne's southeast, last Thursday as he toured Australia promoting the government's budget.
A health official contacted by AAP agreed the order would apply to anyone who was yet to arrive from Australia.
However, a spokesman for Ms Ardern insisted the trip would take place.
"We are in close contact with the Australian government and working through any implications for the visit," he said.
It is likely the NZ government will ask Mr Morrison to produce a negative test in the next two days before boarding "Shark One", the PM's plane, to New Zealand.
The health order requiring people in Melbourne to isolate and test captures around 5000 people currently in New Zealand.
Aside from the legalities, there is one other coronavirus-related hurdle that could stop the prime ministerial talks.
Should Victoria's outbreak escalate dramatically in the coming days, Mr Morrison may decide it's appropriate to stay in Australia.
Mr Morrison is due to leave for the trip on Sunday morning, returning on Monday afternoon.