Terry Mulder said on Friday the Victorian Taxi Services Commission was investigating Uber's ride-sharing practices. The sprouting service, called "low cost", is up to 50 per cent cheaper than a traditional taxi and is already gathering pace in Sydney.

"The TSC is currently investigating this practice and will take appropriate action if such activity is detected in Victoria," Mr Mulder's spokeswoman said. "All taxi and hire car drivers go through a rigorous accreditation process before they are allowed to drive a taxi or hire car – this is for both the safety of drivers and passengers.

"The Taxi Services Commission strongly discourages any members of the public applying for any job advertisements that offer quick cash for providing taxi and hire car services using a private vehicle."

Last week, Uber expanded beyond providing taxis and private hire cars through its app and began letting regular people transport Uber users about in Sydney, Brisbane and Melbourne. To be eligible, drivers must be 24 years old or older, have a driver's licence and no criminal history. They must also own a 2005 or later four-door car that is covered by comprehensive insurance.

Taxi Services Commissioner Graeme Samuel told Fairfax Media on Friday he was surprised and irritated Uber did not approach him and the TSC about its new service.

"I'm surprised because I would've thought that if they wanted some assistance from the Taxi Services Commission to ensure that what they're doing operates within the law or meets the fundamental imperative we've got, which is the safety of passengers, they would sit down with the Taxi Services Commissioner and explain it."

Mr Samuel said his office had tried to contact Uber directly, to no avail.

"To date, they insist on doing that through an intermediary. Well, I'm not going to operate through intermediaries."

On the face of it, Mr Samuel believed that Uber was not complying with the Victorian public transport legislation.

"If they are not complying with the law we'll prosecute," he said.

To comply, Mr Samuel said Uber would need to obtain a $40,000 private hire car licence for unlimited vehicles and have accredited drivers.

Mr Samuel said he wasn't about being anti-competitive, having formerly been the head of the Australian Competition and Consumer Commission.

Instead he said the Taxi Services Commission was about "enhancing" the position of consumers. "I've talked about how for too long strong, vested interests in the industry have dominated the industry to the disadvantage of drivers, operators and consumers," Mr Samuel said.

Uber's new service, which is only available to a select number of Uber users but is expected to be rolled out to other cities and users soon, has infuriated taxi drivers and the NSW Taxi Council. The council says the service puts the public at risk and has called on the NSW government to intervene.

In Victoria, citizens providing taxi and hire car services without the appropriate accreditation are in breach of the Victorian Transport (Compliance and Miscellaneous) Act 1983. Fines of up to $2500 apply if illegal drivers are detected by the Taxi Services Commission, Mr Mulder's spokeswoman said.

"If a member of the public is interested in driving a taxi or hire car, they should apply for the appropriate accreditation via the Taxi Services Commission website," the spokeswoman said.

Victoria's response to Uber's disruptive transport app follows NSW Transport Minister Gladys Berejiklian and her department sending mixed messages over whether the ride-sharing service was legal in NSW.

Ms Berejiklian's department said on Wednesday NSW's Roads and Maritime Services had requested a meeting with Uber to discuss how the NSW Passenger Transport Act applied to the service, and how Uber would respond to its obligations under the act.

Meanwhile, she appeared to concede on Thursday night that there was no problem unless Uber called itself a "taxi service".

"You don't want to limit people's choice because, at the end of the day, it does come down to choice," Ms Berejiklian said on 2GB.