Victorian Premier Dan Andrews has hit out at Australian Prime Minister Scott Morrison over the 17 New Zealanders who flew into Melbourne from Sydney after the travel bubble was opened.

Yesterday it was reported the Kiwis were detained after making the connecting flight because the state of Victoria has not signed on to the arrangement which allows New Zealanders to travel quarantine-free into NSW and the Northern Territory if they have not been in a Covid-19 hotspot in the previous 14 days.

Today, Andrews clarified that the New Zealanders were not detained and haven't "necessarily done anything wrong". He also took aim at the Australian PM, telling a news conference he was "very disappointed" by the situation.

"You would be aware that at around 5.30 yesterday evening, 17 people from New Zealand, having travelled on an international flight from New Zealand to Sydney, were then allowed to board a plane and travel to Melbourne. They didn't spend very long at the airport," Andrews said.

"They left the airport within only minutes, really, of having arrived. Our officers have absolutely no power to stop someone, to detain someone in those circumstances, particularly given they were coming from a very low virus part of the world. New Zealand is and we're very pleased for them, in a very different set of circumstances to the circumstances that we are in in Victoria."

Passengers wearing face masks as they arrive into the international arrivals area at Sydney's Kingsford Smith Airport after landing on Air New Zealand flight number NZ10. Photo / Getty Images

He said authorities in Victoria were now working to contact the travellers and brief them on the situation in Melbourne and the restrictions that are in place.

He added they had "no way of knowing" where in Melbourne the travellers were, because Australian Border Force had not handed over the cards.

"I want to be clear on this, I have written to the Prime Minister this morning and we're disappointed this has happened given that I had written to the Prime Minister on this very issue the previous day, saying at some point we will join that New Zealand/Australia travel bubble, but it is not appropriate now," he said.

"This is effectively possible because we haven't closed our border. I don't think these people could have travelled domestically into other states where borders are closed. That is what the Prime Minister wants.

"We have done that and now we see 17 people turning up on our doorstep without any notice, without any structure, and we still can't get the cards from Australian Border Force as to who these people are and where they have gone."

The Premier says it's "not acceptable" that international arrivals are allowed to travel freely into Victoria when Victorians cannot travel freely around their own state.

"I don't think we ever turned our mind to this happening. Our position had been clear. We are not in the New Zealand bubble," Andrews said.

"At a time when Victorians can't freely move around their own state for the best of public health reasons, it is not acceptable to me that people from another country, when we have expressly said that we don't want this to happen now, are able to get into Melbourne.

Andrews has made clear that, as far as he's aware, the 17 New Zealanders haven't "necessarily done anything wrong".

"That will be looked at, but I don't think so," he said.

Asked if they should be asked to leave, he said it wasn't a matter for the Victorian Government.

"I don't issue visas. I don't control the free movement from other countries into our country and nor do I want to," he said.

"That is a matter for the Commonwealth Government, not a matter for us. The bubble arrangement is a perfectly reasonable thing, but not to Victoria at this time, and that is why we made that point clear.

"It would appear it hasn't gone through down to the level that it needed to and these people have arrived. They themselves haven't done anything wrong in trying to come to Melbourne, but they shouldn't have been allowed to come here because we haven't signed onto the bubble."

"No warning. In fact it is exactly the opposite of what we signed up for. It has happened now, it can't be undone."

Andrews said he stands up every day "making sure every Victorian knows they can't freely move around their own state for the best of reasons, and at the same time we have people being allowed in from another country and we were the last ones to find out about it".

"It doesn't make any sense," he said.