Passengers on a flight from Melbourne to Sydney last night disembarked without being screened by NSW Health officials, in a major breach of the state's coronavirus protocols.

An email from Sydney Airport leaked to the ABC claims Jetstar breached NSW Government health orders by allowing travellers on flight JQ520 that landed at 6.53pm to get off without being checked.

"The final JQ flight arrived and staff enabled disembarkation without NSW Health and police in attendance, breaching the arrivals screening protocols," the email read.

Yesterday, the NSW Government introduced new laws that banned anyone from Greater Melbourne travelling to NSW except under "exceptional circumstances", such as accessing urgent medical care or fulfilling legal obligations.
Coronavirus live news: Follow all the latest information in our blog.The breach means all passengers on the plane — who would be required to self-isolate for two weeks — were allowed into Sydney with no scrutiny.

Screening includes temperature checks and a series of health questions. The traveller's home address in Victoria is also verified, and anyone who appears symptomatic is tested for COVID-19.

NSW chief health officer Kerry Chant confirmed there was "an issue" at the airport.

"The airport have now put in protocols to ensure that the health teams are there and able to do the screening, and no-one is allowed to disembark before that happens," she said.

"All of those individuals are known, obviously you get tickets when you're on a plane, we are in the process of tracing them up, if anyone is found to have travelled in breach of any orders we'll refer them to police and take the appropriate action, depending on whether anyone is symptomatic, to ensure the community is protected."

Jetstar said it had "refined" its disembarkation procedures following the incident.

"We assisted by locating passengers in the terminal who had disembarked without being screened and provided the aircraft manifest to the department to assist them in contacting passengers," a spokesperson said.

Jetstar also said Victoria Health performed temperature and ID checks on passengers before they left Victoria.