There was a recent push within the WA Government for commuters to pay more to use public transport during peak times, Transport Minister Dean Nalder has confirmed.

The ABC understands Treasurer Mike Nahan considered getting the Economic Regulation Authority to investigate how peak-demand pricing could work in WA, with train users targeted in particular.

Peak demand pricing is used in some states and is designed to encourage public transport passengers to travel later or earlier, to help spread demand throughout the day.

Mr Nalder confirmed Treasury considered the move, but said it would not be introduced in this term of Government.

"The Treasurer and I recently discussed it ... I've even had conversations with the Premier regarding the issue but it's not something that I'm keen to pursue right now," he said.

Opponents said increasing fares during peak times would drive people off public transport and worsen Western Australia's congestion crisis.

Curtin University sustainability expert Jemma Green said talk within the Government of peak-demand pricing was another "thought bubble on transport".

"This is a price gouge that would only penalise those trying to do the right thing," she said.

"The Airport Rail Link project is going to run at a massive loss and so the Government is looking at ways that they can get more money from commuters, but it's very short-sighted and it also means that they're more likely to encourage people to travel on the roads and make more congestion."

Transport portfolio in chaos: Opposition

Opposition transport spokeswoman Rita Saffioti agreed any such measure would only increase cars on the roads.

"More chaos in the transport portfolio," she said.

"We need to be encouraging people on trains and on public transport during peak times, not discouraging them."

However while Mr Nalder ruled out peak-demand pricing this term, he said it was a practical measure which he believed would be discussed in the future.

"We still subsidise public transport to the tune of 70 per cent, so it's not a matter of price gouging from a government," he said.

"We've got periods of high concentrations and then we've got long periods where the trains don't have a lot of passengers in, so to try and encourage behaviour where we can spread it a little bit is a wise thing to do.

"But I just believe that it's a distraction for the Government right at this point in time and therefore in the Department of Transport, we're not willing to pursue it at this point in time.

"[But] I think it's wrong for any government to rule it out beyond their own current term."