According to a leak to the Times, Oakervee has concluded that the £88bn project goes ahead in full but he criticises HS2 procurement for shouldering all the risk with little gain.

The leaked document, authored by the former HS2 chairman, is critical of procurement saying that prices have been significantly inflated by contractors.

He says that HS2 “carrying most of the risk and all of the pain with little gain”

Oakervee is understood to recommend changing the excessively expensive contracting model and floats the possibility of re-procuring works for best value.

He also calls on the Government to update and publish a revised business case for the project as a whole.

Oakervee also warns that there are no shovel-ready alternative investments in the existing network to provide for much-needed additional rail capacity.

As well as backing phase one and two, serving both sides of the Pennines, the review is also understood to support plans to integrate it with new rail investment proposals from Midlands Connect.

Contractors waiting for a notice to proceed will have to hang on until the New Year for final confirmation about whether the project will proceed.

The report has officially been locked away until after the general election.