Roe 8 supporters to rally at WA parliament

After months of protests, arrests and concerts by opponents of the Perth Freight Link, supporters of the cancelled highway extension plan to rally when the West Australian parliament resumes.

The Build Roe 8 group, consisting largely of truck drivers who want the road built for safety, will deliver a petition with more than 8000 signatures to Opposition leader Mike Nahan to present during the first sitting day for the new McGowan government.

Steven Portelli, a key figure in organising Thursday's midday rally, is also a councillor for the City of Cockburn, which supported protest groups Save Beeliar Wetlands and Rethink the Link in fighting the road.

Mr Portelli told AAP on Wednesday he expected a crowd of up to 100 Roe 8 supporters.

About 20 large trucks were originally organised for the protest as a statement backdrop but had to be cancelled due to beefed-up security for the first day of parliament, he said.

Transport Minister Rita Saffioti said $85 million had been spent on the Perth Freight Link, including clearing work and scrapping the project.

The controversial $1.2 billion Roe Highway extension was proposed by the former government but faced stiff opposition from community groups that challenged its legality based on environmental conditions.

The Barnett government won the right to build the highway just before the March state election but new Premier Mark McGowan promised to stop the project.

The WA Liberals are still calling for the road to be built and have support from their federal counterparts.

Treasurer Scott Morrison remains supportive of the highway extension despite redirecting $1.2 billion of Commonwealth funding previously flagged for the Perth Freight Link to McGowan's Metronet project to expand the Perth rail system.

"If there's a state government that wants to do that in the future then we'll be there," he told 6PR radio on Wednesday.

Ms Saffioti says 231 workers from the Roe 8 highway extension will be moved to three other road projects, which will cost $276 million.

The contractors involved have welcomed the new projects and say they will help rehabilitate the cleared Roe 8 site in Coolbellup.