The NSW Rural Fire Service on Monday evening said it had given approval for the fireworks display to go ahead in Sydney Harbour.

"The Sydney Harbour fireworks have been approved to proceed tomorrow," the RFS said on social media.

"The NSW Rural Fire Service and Fire and Rescue NSW are assessing a number of other total fire ban exemptions."

NSW Deputy Premier John Barilaro earlier called for New Year's Eve fireworks in Sydney to be cancelled, saying it's a "very easy decision".

Temperatures around the state are expected to peak on Tuesday, with forecasts of more than 40C across western Sydney and in regional NSW.

Parramatta, Armidale and Huskisson are among suburbs and regional towns that have cancelled or postponed their fireworks displays due to elevated fire risks.

"The safety of our community and general public is important to us and it was decided that the event could not proceed without compromising this safety," the City of Parramatta said on Facebook on Monday afternoon.

Meanwhile, North Sydney Council will not allow the forested headland Balls Head Point to be used as a vantage point for the famed display on the capital's harbour.

The NSW National Parks and Wildlife Service also announced on Monday evening that the popular Bradleys Head and North Head viewing points would be closed during the Sydney fireworks due to "extreme bushfire risk".

Mr Barilaro on Monday echoed calls from 250,000 people who have signed a petition seeking the Sydney fireworks to be scrapped and funds redirected to drought and bushfire relief.

"The risk is too high and we must respect our exhausted RFS volunteers. If regional areas have had fireworks banned, then let's not have two classes of citizens. We're all in this crisis together," he said on social media.

However, City of Sydney spokeswoman Tanya Goldberg says the council is of the "firm view" the event should proceed.

The city's famous celebrations are expected to attract one million people to the harbour foreshore and generate $130 million for the NSW economy.

Premier Gladys Berejiklian has said if the RFS and experts say it's safe for fireworks to go ahead, then they should.

Sydney, the Hunter, the Illawarra are among more than half of all NSW fire districts subject to a total fire ban on Tuesday.

The ban means the RFS must exempt any operators wishing to undertake fireworks displays.

The fire authority has also warned residents to shelve any private fireworks plans.

NSW Police assistant commissioner Michael Willing said the harbour fireworks were not a matter for police to determine.

He encouraged revellers to take care in the heat and remain hydrated, and said police would work alongside emergency services such as NSW Ambulance.

Some 3000 police officers will be on duty around the harbour foreshore.

Australian Associated Press