A commitment to planning for the F6 extension in the new Illawarra Regional Transport Plan was not "definite", Kiama MP Gareth Ward said on Monday.
The plan, released on April 1, identifies the F6 extension as "a long-term priority".
"We will undertake further planning to prepare for the future F6 motorway connecting the Sydney Motorway Network and the Illawarra region," the plan stated.
Mr Ward is one of seven Liberal MPs petitioning the government to get a move on with the F6 extension.
He said the mention in the transport plan was "not definite".
"What we want is the money that we require to progress that project now," Mr Ward said.
"The campaign we've launched is that we want this project to be shovel ready in two years.
"I'm not excited by a commitment that we may have it ready into the future. That's not what our campaign is about - we want some certainty so this project can be moved up the list where it deserves to be."
Mr Ward said he was not suggesting the F6 extension should jump ahead of the Albion Park Rail bypass.
Since the announcement of the petition in late March there has been a degree of cynicism about the move, with some suggesting Mr Ward could have lobbied his government behind the scenes rather than take a public stance.
"I have done that," he said about working behind the scenes.
"That's one of the reasons I'm launching the petition. I've put pressure on the government behind the scenes and I'm not satisfied that we've been able to get to the point where we can make an announcement.
"If we had the money we would announce it, but we haven't."
He also rejected the suggestion that the petition was nothing more than a political stunt.
"I'm using what I consider to be a political instrument to put pressure on my own government," he said.