The prospects of MAX light rail becoming a reality have taken another hit after Transport Minister Dean Nalder found two similar transport systems in Singapore to be unviable.

Mr Nalder has returned from a fortnight-long ministerial research trip to New Zealand and Singapore, where he met representatives from SBS Transit, the company behind the Asian hub’s twin light rail systems.

Mr Nalder, who is evaluating whether a future rapid transport link between the CBD and Mirrabooka will be a light rail as promised or cheaper buses, described the meeting as “interesting”.

“In talking to the company that runs the two light rails in Singapore, they indicated that they haven’t been able to make it work and they wouldn’t be building additional light rail in Singapore,” he said.

It comes as Premier Colin Barnett last week told Seven West Media light rail “hasn’t been an overwhelming success in Australia at all”.

“The project for example recently completed on the Gold Coast in Queensland really has not been successful ... so there’s a bit of rethink about light rail,” he said.

The comments were in stark contrast to the Premier’s support for light rail before the 2013 election, when he described the $1.8 billion MAX as “the greatest advance since the electrification of the Perth rail network” before shelving it nine months later.

Former transport minister Troy Buswell was similarly emphatic before the election that “light rail has been assessed as the most suitable option in these areas as it can move many more people in one lane than any number of buses and cars”.

Acting shadow transport minister Paul Papalia said the Liberals were totally confused on public transport.

“It’s laughable that Barnett Government ministers are flying around the world at taxpayers’ expense desperately searching for justification to break their election promises,” he said.

Mr Nalder’s finding came after a $14,000 trip by Mr Buswell to Europe in August and September 2013 resulted in a report endorsing light rail, Mr Papalia said.