An Australian art teacher has reportedly jumped through a loophole in the trans-Tasman travel bubble to return to a job in Moscow and his girlfriend.

Tim Byrnes flew to Auckland last week and caught a flight to Istanbul on Friday night to travel on to Russia, the Sydney Morning Herald has reported.

"I've escaped. I get to go back to my life," said Byrnes, who said he had encountered several other people in Auckland who were watching his progress and hoped to do the same.

According to the Australian Financial Review, Australian and Kiwi border officials have confirmed a loophole of sorts does exist for Australians willing to fly into New Zealand and book a flight to a third country.

Since March last year, Australian citizens and permanent residents have required an exemption to travel overseas as part of the country's measures to fight the Covid-19 pandemic, on the basis they could import the virus when they return.

People travelling to countries not considered high risk can request an exemption from the travel ban for compassionate reasons, to conduct urgent business, or if they are travelling for longer than three months. Exemptions are hard to obtain.

Under the Biosecurity Act, failure to comply with an emergency determination can bring a fine of up to $66,000 or five years imprisonment or both.

Health Minister Greg Hunt told the Sun-Herald the exemption to the international travel ban "only applies where a person is leaving Australia to travel to and stay in New Zealand, not where the traveller intends to travel to New Zealand for the purpose of . . . travelling to a third country."

"Travellers should be aware that international travel to any other country continues to pose a significant risk to public health."

The official advice to New Zealanders, issued through the Ministry of Foreign Affairs and Trade, is not to travel overseas at this time because of the Covid-19 pandemic and associated health risks.

The "Do not travel" advisory does not require New Zealanders to obtain an exemption, like Australia, but sets out the risks of travelling overseas, including the possibility of limited health care, difficulties obtaining travel insurance and undertaking and paying for quarantine.

A New Zealand Customs spokeswoman told 9News it had "no power" to stop Australians travelling onwards.

"This is a domestic issue for the Australian Government's Department of Immigration and Border Protection," she said.

In another case reported by the Sydney Morning Herald, Elaine, from Sydney's northern beaches, who requested her last name be withheld, said she was in "total despair" about being separated from her family in Britain and planned to leave via New Zealand if she could not get an exemption.

Byrnes returned to Australia for a legal matter in January last year and was visiting his parents in Tamworth when the borders closed.

Australians who are ordinarily resident overseas - based on their electronic travel records - do not require an exemption to leave but Byrnes did not realise this was the case until he had been there six days over the time limit. He then applied for an exemption to leave, since he had a job in Moscow.

Byrnes said he did not plan to return to Australia until after the pandemic and was not concerned about potential penalties from the Australian Government.

"Once the biosecurity threat goes, I think it's a chapter that the government will probably want to forget," he said.