NSW Police will be able to fine individuals $1000 and businesses $5000 for breaches of public health and ministerial orders during the coronavirus crisis.

Police will have the power to issue $1000 on-the-spot fines to people caught flouting self-isolation or social distancing requirements in NSW during the coronavirus pandemic.

The move comes after Prime Minister Scott Morrison announced tougher restrictions to try and slow the spread of the disease in the Australian community.

NSW police officers from Thursday will have the power to hand out fines of $1000 to individuals and $5000 to businesses that breach public health orders or ministerial directions, Commissioner Mick Fuller announced on Wednesday.

People in the firing line include returned travellers who contravene the requirement to self-quarantine for 14 days and those diagnosed with COVID-19 who similarly don't follow the rules.

Fines will also apply for breaches of the prohibition on outdoor gatherings of 500 people and indoor gatherings of 100 people.

"The police needed to stand up and say the community have to take this seriously, or more people will be affected and this virus could run on for many, many more months," Mr Fuller said.

Police have the power to apply penalties already in place under the Public Health Act, which means people can be jailed for six months and/or issued a fine of up to $11,000 if convicted.

There'll be an increased police presence with officers conducting random checks on people who have been reported as possibly breaching quarantine requirements, NSW Police Minister David Elliott said on Wednesday.

"We need to kill this virus before it kills us," he said.

Mr Elliott didn't rule out introducing additional penalties either.

"We don't rule out any further developments when it comes to the enforcement of these regulations, everything is on the table."