But opponents to the $1.65 billion road say they remain up to the fight.
Last Wednesday the Supreme Court ruled that conditional approval granted by the WA Environmental Protection Authority (EPA) for Roe 8 was invalid.
Roe 8 is a 5km extension from Kwinana Freeway to Stock Road via Beeliar Wetlands and the first stage of the PFL.
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READ NOWThe State Government was believed to be close to signing contracts with a consortium to begin work on Roe 8 early in 2016.
But after a crowd-sourced legal bid to review the decision, Chief Justice Wayne Martin placed a roadblock in front of the controversial project.
He said the EPA “took no account of its own published policies at the time it made its decision and provided its report to the Minister” and concluded the environmental impact assessment undertaken by the EPA was invalid.
Premier Barnett said he was disappointed with the decision but the State Government was likely to take stock of the situation and try again.
“We’ve yet to have time to really study the full implications of (the decision) but my best guess at this stage is that it will mean the State Government will need to re-do all or part of the environmental approvals for Roe 8,” he said.
“If we have to re-do it that’s what we will do and the project will proceed.”
Rethink the Link co-convener Kate Kelly described the court decision as a victory for the community and for justice.
“We know there could be more challenges to come but for now we know our wetlands are safe,” she said.
“Our support will remain steadfast and resolute. We know no matter what now we have the community behind us.”
She said the PFL should be scrapped in favour of “the logical alternative” – an outer harbour.
Cockburn Mayor Logan Howlett said the crowd-funded campaign to challenge the approvals process reached an incredible result.
“We call upon the State Government to take note of this decision to the Rethink the PFL and move to developing the Outer Harbour as a priority,” he said.
Federal Labor MP for Perth, Alannah MacTiernan, called for the Federal Government to ditch its $925m funding for the project in favour of ready-to-go rail projects.