Warren-Blackwood MLA Terry Redman moved a motion in parliament on Wednesday, November 13 condemning the state government for risking job opportunities in the South West tourism and small business sectors.
Mr Redman said the government had actively opposed the development of a new terminal at the Busselton Margaret River Airport.
He said the regional development minister had made all sorts of excuses why she would not fund the terminal despite having said they would if the City of Busselton secured an airline.
"What we have found out now is that twice the government has changed the financial assistance agreement with the city," he said.
"They seem to be moving the ground rules as they move forward, they are changing the goalposts."
Mr Redman said conversation around the flights shifted with the government calling the service a trial.
A note to the regional development minister's chief of staff from the South West Development Commission stated, "I am of the view that the service needs to operate on a trial."
Mr Redman said that was the first time a trial idea had been laid into the debate.
"Despite the minister saying if you get an airline they will give a terminal, they are now layering in all these other barriers to it making it hard for them."
Regional development minister Alannah MacTiernan said they were always focused on attracting flights to Busselton.
"That was the whole purpose of this project," she said.
"Our government has succeeded where the previous government could not - we've secured the first ever direct flights from the East coast to the South West, and tickets are running out the door.
"The State Government has spent $43.25 million towards the development of the airport and airline attraction, and will invest a further to $3.265 million to upgrade terminal infrastructure to allow Jetstar's air service to commence in March 2020.
"This decision was agreed by Jetstar and the City of Busselton to ensure the airport is fit for purpose for this service.
"Jetstar made it very clear to our Government before the deal was finalised that a new terminal was not required for this service.
"No other airline was prepared to commit to the route. There is no business case that can be made for a new terminal at this time.
"We need to be clear that this service is a three-year agreement and has a generous subsidy built in: at the end of the period, Jetstar and the City of Busselton will decide if the flights are financially viable.
"We want to see this route succeed and become sustainable, and will consider further investment into the terminal if required in future.
"The Nationals should be celebrating this achievement of our government: instead they continue to talk down the region."
In parliament, Vasse MLA Libby Mettam supported Mr Redman's motion stating an FOI document she obtained indicated the minister's agency was looking at ways in which it could unpick the airport expansion project.
"That is pretty damning," she said.
Ms Mettam said if any of the Rio Tinto flights from the Pilbara are delayed there could be a situation where 400 people would be going through the terminal, which was built for 100 people.
"That is not a good tourism experience," she said.
"That is not putting forward the best interests of tourism in WA.
"That is certainly undermining the interest in growing the tourism outcomes for the Busselton-Margaret River region and the greater southwest region. Twelve local governments support this project."