A special deal guaranteeing hundreds of millions of dollars of compensation for the dumped East West Link was initially drafted by the consortium contracted to deliver the $6.8 billion toll road, which would ultimately benefit.

Senior sources close to the project have confirmed the Napthine government was so keen to reassure East West Connect it would get its money following a Labor promise to scrap the project it asked the consortium to draft a so-called side letter guaranteeing taxpayer-funded compensation even in the absence of a valid contract.

The revelations came as Treasurer Tim Pallas accused the former government of needlessly bringing forward a multibillion-dollar deal to finance the project to deliberately sabotage Victorian taxpayers.

In an extraordinary claim, Mr Pallas has told The Age the so-called financial close - securing the funding needed to begin work on the project - could have happened under the contract as late as December 5, about a week after the state election.