West Australian Transport Minister Dean Nalder believes voters will trust the Barnett Government on the key issue of transport, despite breaking its promise to build the Max Light Rail link to Mirrabooka.

Mr Nalder and Premier Colin Barnett have officially opened the new $217 million underground Yagan Centre bus port on Wellington Street in Perth's CBD, showcasing the Government's latest transport project.

"There's a lot of things that have gone into this bus port to ensure we actually deliver a first-class or customer-first public transport experience," he said.

The bus port will be open to the public on Sunday, and features an air-conditioned, airport-style lounge and new bus allocation system using stands which Mr Nalder said would improve efficiency and help reduce transit times.

It is expected to handle 28,000 passenger journeys a day.

Since coming to office in 2008, the Government has completed a string of major transport projects, from the $1 billion Gateway project around Perth Airport to freeway extensions, rail line extensions and construction of new highway overpasses.

But it has also been heavily criticised for failing to deliver on its promise to build Max Light Rail link to Mirrabooka, and for its handling of the Perth Freight Link to Fremantle.

Despite that criticism, Mr Nalder remains convinced the public will judge the Government on what it has delivered, rather than what it has not.

"There are major infrastructure projects across all modes of transport, including road and cycling. And I believe this government has every right to be proud of what it's delivering for Perth and Western Australia," he said.

Mr Barnett said the completion of the new bus port was another important milestone in the City Link project which would link the Perth CBD with Northbridge.

He said despite the axing of Max Light Rail, servicing the northern suburbs remained a priority.

"The idea of providing improved public transport for those northern suburbs is still at the top of the list for the State Government," he said.

He said the Government's long-term transport plan, to be released later this month, would set out a new proposal.