POLICE say they will make travelling between Victoria and New South Wales as easy as possible for people living in "border bubbles".
All border crossings are expected to close from midnight Tuesday night following a "concerning spread" of COVID-19 in Melbourne.
Australian Defence Force personnel have been deployed to assist NSW Police to shut down 55 border crossings into Victoria, a closure that is likely to last for weeks.
NSW Police said aerial surveillance would also be used to monitor border crossings and conceded the next 72 hours would be a challenge.
NSW Police Commissioner Mick Fuller said he accepted that border communities would be upset and businesses disrupted, but urged residents to "work within the spirit" of trying to bring COVID-19 under control.
Mr Fuller said Service NSW would begin issuing exemption permits from late today, but urged people who did not need to cross the border not to.
He said trucks and other heavy transport would be "green-lighted" through border road blocks.