Galliford Try’s £90m M56 job near Manchester Airport and Costain’s £150m M6 contract between Warrington and Wigan had been due to start a year ago but were delayed to reduce congestion caused by roadworks in the region.

Now sources say cost overruns on other smart motorway projects have prompted Highways England to review procurement plans.

One insider told the Enquirer: “There is a strong feeling Highways England will now deliver these projects through its Smart Motorway Alliance partners, when these are finally announced.”

The alliance procurement approach will improve transparency between Tier 1 and Tier 2 contractors.

Highways England was due to reveal its three preferred contractors to deliver the future smart motorways last December but the latest Agency procurement plan now says first contracts will be awarded in the Spring.

There is further uncertainty because of the Government safety review into smart motorways as a result of a sharp rise in near misses.

It is looking at the frequency of emergency refuge areas which were placed 500m apart on the first M42 pilot scheme, but can be 2.5km  apart on stretches of the M25.

Should the programme be given the all-clear to re-start Balfour Beatty is widely speculated to be one of the three partners, with Costain and BAM Morgan JV though to be in the running.

A Highways England spokesperson said:  “The Department for Transport is considering a range of evidence during its stocktake.

“We expect the results to be published shortly and to provide the most up-to-date assessment of the safety of smart motorways. We are committed to implementing any new recommendations as part of our ongoing work to make our roads even safer.”