It comes as a girl was airlifted and two adults taken by road to hospital after a two-car collision near Pomborneit on Monday.

The Princes Highway Action Alliance's Stephen Lucas said he was "very disappointed" money for the highway remained stalled 16 months after the federal government announced it.

The money includes $60 million for upgrades between Warrnambool and Port Fairy, $80 million for the Green Triangle area and funding that would see changes to the Blue Church intersection near Colac.

But agreement between the state and federal governments to start the work is yet to occur.

"It appears that the state is unwilling to contribute their 20 per cent of the funds," Mr Lucas said. "It is extraordinarily frustrating."

The alliance will launch a television commercial in coming weeks on local networks ahead of the state budget likely to be in May.

"The focus will be that the state government needs to contribute money toward getting these works started," Mr Lucas said.

He said the community had become "confused" why the money was not being spent.

"People just don't understand why we are getting all these announcements and then nothing happens," Mr Lucas said.

"It is just sinking into a black hole and has been doing that for three years while we are watching the roads deteriorate.

"You have to make your own judgement as to why it would be. But it is bizarre."

He said the road edges were deteriorating due to heavy vehicle traffic.

"Maintenance is just not keeping up with the damage," Mr Lucas said.

A Victorian Department of Transport spokeswoman said an agreement was under way.

"We're continuing to finalise arrangements with the Commonwealth to progress joint funding and planning for work committed along the Princes Highway West."

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