Australia's Federal Government says "there was an understanding" that travellers who arrive in New South Wales from New Zealand would be allowed into other states if their borders aren't closed, despite Victoria Premier Daniel Andrews stating Victoria was not part of the new trans-Tasman travel bubble.
Seventeen passengers flew from New Zealand to Sydney yesterday, on day one of the new trans-Tasman travel bubble, then caught a connecting flight to Melbourne.
Passengers from New Zealand now do not need to quarantine upon arriving in New South Wales, but Victoria Premier Daniel Andrews says his state was not part of the bubble arrangements.
"Somehow, something has gone wrong at Sydney, I think, to allow people to travel on beyond the international flight."
He said Victorian officials had "absolutely no power" to detain them.
The premier said he had written to Prime Minister Scott Morrison to ensure more arrivals from New Zealand do not travel on to Victoria on Sunday.
"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.
However, the Federal Government has made a statement contradicting the claim that travellers from New Zealand should not be allowed to fly into Victoria.
Acting Immigration Minister Alan Tudge said when the trans-Tasman travel bubble was discussed at a Australian Health Protection Principal Committee (AHPPC) meeting on Monday, "no official from any jurisdiction raised concerns" about arrivals from New Zealand potentially travelling to other destinations.
"There was an understanding that when Kiwis arrived into Sydney, coming from a country which has zero community transmissions, that there'd be no need for quarantining," he said.
"And that once they had arrived into Sydney that they would be treated like any other person in New South Wales, any other Australian, any other visa holder, and therefore travel into those jurisdictions which enable people to travel into them - and that of course included Victoria."
Victoria has not accepted international arrivals since early July, but its domestic borders have remained open.
When asked whether Victoria should consider shutting its domestic borders, Andrews said he did not want to do that.
"I know that the prime minister would be very disappointed if that happened," he said.
"That is what he is trying to avoid, and that is why I wrote to him this morning and made it clear that we need to get to the bottom of this, and have the requisite assurances that this won't happen again."
Earlier, Victoria Police said they would visit the travellers later today to perform welfare checks.
Police Deputy Commissioner Rick Nugent said the passengers were in Melbourne and not under any detention orders.