Anyone attending an organised Invasion Day rally in Sydney on Tuesday faces a fine and even jail time.
NSW Police Minister David Elliott said it was a breach of the public health orders.
“It’s as simple as that,” he told 2GB’s Ben Fordham.
“If 1000 veterans got together tomorrow to celebrate Australia Day, they’d be in breach as well.
“Unfortunately, anyone who attends tomorrow will be exposed to fines and imprisonment.”
More than 2700 people have said they are attending an organised rally at The Domain on Tuesday.
But organisers argue the event will follow strict safety protocols.
“We request you do not attend if you have any flu-like symptoms, wear a mask and practise social distancing,” they said on Facebook.
Under current health restrictions, no more than 30 people can gather in groups outdoors.
Mr Elliott also blasted the ABC for listing the Domain protest as “one of the biggest Invasion Day events”.
In a company-wide memo on the day’s happenings, the public broadcaster referred to the day as Australia Day/Invasion Day.
ABC News also tweeted: “What to do on Australia Day/Invasion Day in 2021.”
The network has since been accused of dividing the nation.
“If you ever wanted evidence the ABC is out of touch with reality then yesterday was exactly the case … with the ABC to take it upon themselves to change the name (from Australia Day) to Invasion Day just goes to show how out of touch they are with Australian society,” Mr Elliott told the radio station.
He described the move as breathtakingly irresponsible.
“I’ll be making a formal complaint against the ABC,” the Police Minister said.
“If you‘re going out there advocating for some sort of illegal activity or an event that would be in breach of a statute or more. Well, then you’d be called to account.”
Police will be out in force on Tuesday, and Assistant Commissioner Michael Willing said people should be patient and plan ahead.
“People may be marking the day differently, but as with any major event, police will still be out and about across the state focusing on public safety, alcohol-related crime and anti-social behaviour,” he said.
“Police aren’t here to disrupt any plans, but we do have the power to ensure that the community is adhering to the current public health orders, including restrictions on gathering and movement and the wearing of mandatory face coverings in certain settings.”
The police operation will extend to the state’s waterways.
Marine Area Commander Acting Superintendent Joe McNulty reminded people to comply with the maritime laws and ensure they had all the required safety equipment on-board.
“We will also be conducting drug and alcohol testing on the water, so remember, the same rule applies as if you were driving a vehicle. It is a 0.05 alcohol limit,” he said.
“Drinking alcohol or taking drugs while out on the water can end in tragedy, so look after your friends and family and act responsibly.”
Temperatures are expected to reach 35C in the city on Tuesday.