Nowruz is usually a time when tens of thousands of Iranian Australians come together to celebrate the start of the Persian New Year.

Key points: A major Nowruz event in Sydney has been cancelled for the first time

A major Nowruz event in Sydney has been cancelled for the first time Restaurants have taken a hit with customers cancelling bookings

Restaurants have taken a hit with customers cancelling bookings Armita Adili said Iranian Australians aren't in the mood to celebrate

But this year the celebrations will be more low-key as public events across Australia have been cancelled due to coronavirus fears.

One major event planned for this Friday in Silverwater in Sydney's west has been called off at the last minute due to mounting concerns.

Event organiser Roya Malikooti said the festival, which has been running for the past 15 years, usually hosts 400 members of Sydney's Iranian community.

"The decision to cancel the Nowruz event was very difficult, we've never cancelled it before," she told the ABC.

"But we felt in the current situation, it was not wise to gather hundreds of people together in one hall."

It was one of many Nowruz celebrations across the country that have been scrapped.

Restaurants have taken a hit because of coronavirus. ( ABC News: Lydia Feng )

Last week, organisers of the Persian Family Fire Festival in Doncaster in Melbourne's north east announced the annual event would no longer go ahead due to health concerns.

An estimated 7,000 people were due to attend and organisers had already spent $10,000 on hiring the grounds, marquees and advertising.

Australian Iranian Society of Victoria President Sahar Gholizadeh said the non-profit organisation had spent seven months planning the free event.

"It is very sad. We were looking forward to going through with this but obviously always the community's health and wellbeing is our priority," she said.

Tickets have had to be refunded to those attending public Nowruz events in Brisbane, Adelaide and Perth.

Restaurants have also been taking a hit as customers cancelled Nowruz bookings.

Reza Montazeri says reservations have dropped at his Sydney restaurant. ( ABC News: Lydia Feng )

Persian Basement owner Reza Montazeri said reservations had dropped significantly at his popular Iranian restaurant in Sydney's Lane Cove.

"Last Saturday, we had 163 guests. We were full, we had a whole program and everything was fine, compared to now we have just 40 people," Mr Montazeri said.

"Nowruz is usually the busiest time in the year for my restaurant … however, because of the coronavirus we expect to lose a lot of money."

Iran is one of the countries hit hardest by COVID-19 with about 300 people killed and more than 8,000 infected.

Armita Adili from the Iranian Australian Community Organisation said coronavirus fears here, combined with concerns for family members back home, were causing this year's Nowruz celebrations to be far more muted.

Armita Adili says celebrations this year will be more muted. ( ABC News: Lydia Feng )

"The Iranian community want to show their solidarity with the people of Iran because of the high levels of infection and deaths as a result of COVID-19."

She said many Iranian Australians were not in the mood to celebrate, like previous years.

"Instead the celebrations are going to be low-key. People are going to gather together in small groups, maybe at home with family or friends."

Nowruz is observed by all Persian communities, including those in Afghanistan, Armenia and Turkmenistan.