UPDATE: The Federal Government has vowed to pull $1.2 billion of funding if the Perth Freight Link does not proceed.

Announcing he would cancel Roe 8 and the Perth Freight Link if he was elected this morning, Opposition Leader Mark McGowan declared his intention to earmark $1.7 billion set aside for the project to other transport priorities.

But a spokesman for Urban Infrastructure Minister Paul Fletcher said the funding could not be reallocated.

“The funding is for the whole Perth Freight Link project and is specific to the project. It cannot simply be ‘re-allocated’ to other projects,” the spokesman said.

“Perth Freight Link has been assessed by the Government’s independent infrastructure adviser Infrastructure Australia as a high priority project addressing national connectivity issues.”

McGowan earlier unleashed his boldest policy ahead of the March State election, vowing to scrap Roe 8 and the Perth Freight Link, while redirecting the funding to other “congestion busting” road projects.

Roe 8 is a highway to nowhere. It is a monumental waste of taxpayers’ money.

Mr McGowan says he will cancel and renegotiate the Roe 8 contract and has informed the contractors that they should do everything in their power to minimise the costs they incur building the road between now and the election.

The decision comes after Labor obtained legal advice from former State Solicitor Grant Donaldson SC, who examined the redacted Roe 8 contract tabled in Parliament and believes any liabilities to the State from termination would be “limited”.

In his advice, which Labor released today, Mr Donaldson highlighted a clause in the contract which allows the Commissioner of Main Roads to terminate the agreement at any time.

Mr Donaldson's advice is that clauses of that nature are not always seen in agreements of this kind.

“I assume the commissioner insisted upon the inclusion of such a term having regard to the announced intention of the Opposition to review the project if it forms Government and the proximity of the next election,” Mr Donaldson wrote.

Labor has pledged three new road projects to be funded from the savings of cancelling Roe 8:

* Bringing forward the $145m duplication of Armadale Road between Anstey and Tapper roads.

* Building a $166m bridge linking Armadale and North Lake roads over the Kwinana Freeway.

* Spending $95m to build two overpasses on Wanneroo Road over Ocean Reef Road and Joondalup Drive.

Mr McGowan said Labor had settled on a position that it believed was in the best long term interests of the State.

“Roe 8 is a highway to nowhere. It is a monumental waste of taxpayers’ money,” Mr McGowan said.

Play Video A massive protest over the Roe 8 extension has been cancelled. The West Australian Video A massive protest over the Roe 8 extension has been cancelled.

Transport Minister Bill Marmion said Labor's decision was “reckless and costly”.

Mr McGowan said it did not make sense to spend billions to build a “truck highway” to Fremantle Port, which he believed would fill in ten years.

Instead, Labor will commit $20 million to planning a new outer harbour in Cockburn Sound, and container numbers at Fremantle would eventually be capped.

Labor also plans to boost the subsidy paid to put containers on rail out of Fremantle, rather than on trucks, which it argues will immediately take trucks off the roads.

In all, Labor plans to use $236 million of Roe 8 money on the three new projects it has announced, with the balance of their total $406 million cost already allocated in existing funding commitments.

Labor is banking on using the full $1.7 billion allocated to the Perth Freight Link project for other transport priorities - even though the vast bulk of that cash is from the Federal Government and pledged specifically to the PFL project.

Asked why he was confident that the Federal money would not be withdrawn if PFL was abandoned, Mr McGowan cited the precedent in Victoria when that State's incoming Labor Government cancelled the East-West Link road project.

Camera Icon The Roe 8 and Perth Freight Link projects have been the target of numerous protests. Credit: The West Australian, Ian Munro/The West Australian

“The Commonwealth dedicated its contribution (to East-West Link) to other congestion busting projects in Melbourne and Victoria,” Mr McGowan said.

“If the people of WA, on March 11, vote in favour of Labor, they are voting in favour of our plans for this project and we would expect - in fact demand - that the Commonwealth respect the will of the people of WA.

“Woe betide any Federal Liberal Government that's already ripping us off on GST to rip more money out of WA.”

Mr McGowan said that Federal Liberal candidates had already campaigned in favour of building the three new projects Labor was proposing.

Greens MLC Lyn MacLaren said it was about time Mr McGowan came to the party.

“I’m pleased the ALP has finally bowed to pressure from the Greens and the community to rule out Roe 8 once and for all,” Ms MacLaren said.