Construction on the multi-billion-dollar West Gate Tunnel project is set to grind to a halt after being blocked by the Victorian Parliament's Upper House when the State Opposition worked with the Greens to revoke planning approval.

The $6.7 billion project would see twin tunnels built under Yarraville between the West Gate Freeway and the Maribyrnong River to ease congestion in Melbourne's west.

It is set to be funded by a controversial deal that will see toll road operator Transurban contribute $4 billion to the project, in exchange for extending tolls on CityLink — on the other side of the city — for another decade.

The Coalition and the Greens today voted 22 to 18 to block planning changes needed for the project.

Roads Minister Luke Donnellan said that meant work had to stop, but it may start again as soon as Thursday when the Government re-gazettes the planning approvals.

"I can assure you we have a way through. We will reintroduce the planning scheme again. We will gazette it again and this project will continue," he said.

"I've indicated we have pathways through and we will assess those when we need to assess them. In many ways it's the actions taken by the Upper House which will dictate which pathways we [actually use]."

Once those changes were gazetted, the Upper House could simply revoke them again.

But the Opposition's David Davis would not say whether the Coalition would put up another revocation motion.

"We can't control what the Government does now. But what is clear is that this project is not in the community interest," he said.

Greens MP Sam Hibbins said they would revoke planning approvals again if the Government did not make significant changes.

"We're opposed to the West Gate Tunnel. And if the Government is just going to bowl up the exact same project, well, of course we're going to oppose it," he said.

Ahead of the vote, Premier Daniel Andrews said it would not stop the tunnel being built.

"There's 700 people working on this project right now," he said.

"This is not some phantom project like we had dished up to us with contracts and side letters signed before the last election.

"We have alternative pathways. This project is getting built because it needs to be built."

Neither the Premier or Roads Minister Luke Donnellan would say what those "pathways" would be.