Preparation for the Bussell Highway dual carriageway has begun despite no secured funding to finish the project.
The $4.5 million works involve first lane preparations for the five-kilometre stretch between the Capel Bypass and Hutton Road and are expected to be completed by early next year in preparation for the final construction.
According to the state government, the final construction works could start in late 2020.
However, the progression of the project is still subject to the federal government agreeing to contribute 80 per cent of the total cost.
Transport Minister Rita Saffioti confirmed the state government would continue to lobby the federal government, but would not 'sit still' in the meantime.
"I have written to the federal minister requesting that some of the $1.2 billion set aside for the flawed Perth Freight Link project is redirected to this project," she said.
"Completing these pre-works now will mean once funding is secured, we will be ready start work faster.
"Once complete, the Bussell Highway will be able to better cater for holiday traffic, while also improving overall safety and normal daily travel times between Bunbury and Busselton."
During a site visit early on Wednesday, October 2, Bunbury MLA Don Punch said he did not see any difficulty with state and federal partnership proceeding to complete the dualling of the busy highway, which has long been called for by the community.
"It would be very, very hard to see no funding secured because we know that this road is a very dangerous road as it is currently configured," he said.
"It needs to be dual-lane, and I can't see any other resolution.
"Mick [Murray] and I both get a lot of feedback from our community about this road.
"I think local government has been calling for this to be built for a long, long time, too.
"We're all about connecting people in the bush and we know how important safety and road sufficiency is to regional communities.
"It's a great day, it's great to see the machinery out here and it's great to see a partnership between Fulton-Hogan, BCP and Kaartdijin and local employment on this project."
Vasse MLA Libby Mettam said there was no reason the state government could not deliver the full duplication of the Bussell Highway as part of the Bunbury Outer Ring Road project, given the federal government had already committed $680m in funding.
"The community have been campaigning hard for this, which included petitions with over 6,000 signatures and I welcome the commencement of pre-construction works for stage one," she said.
"It is extraordinary that several months after making the commitment as part of the State Budget for this pre-construction work, the Minister for Transport has not secured the additional funds available as part of the Bunbury Outer Ring Road project."
Having seen the frustration the road had caused first-hand, Collie-Preston MLA Mick Murray said he was pleased to see the works finally commence.
"It's great to be here today and we do know the frustrations that this section of road has caused over the years," he said.
"Even last weekend, there was a traffic jam out here.
"To have this work started is very, very important - not only for the locals, but for the tourism industry as well. People from Dunsborough, Margaret River don't want to be in traffic jams.
"To be able to be part of that is quite thrilling.
"We should certainly see some of those frustrations taken away for those travelling on this road.
"Certainly the Capel Shire has been very supportive and both the chief executive officer and the shire president have supported us in our deliberations and trying to get this job up and running."
With increased truck movements expected along the highway in the coming months, the state government urged southbound travellers to plan their journey in advance.