The £1.5 billion upgrade of the A14 is still expected to be completed by this spring, despite the Coronavirus pandemic.
Construction workers are remaining on site at present, but Highways England, which is behind the long-awaited project, is reviewing how it operates on a daily basis to make sure it is in line with Government advice as it comes in.
Staff are working from home where they can, but this is clearly impossible for hundreds of construction workers to do.
Progress on the new road has been dramatic, with the 12 mile Huntingdon bypass stretch opening in December, a year ahead of schedule.
A spokesman for Highways England said: “Staff are working from home where possible, with construction staff still attending site and the project still on course to finish by the spring.
“Our working practices are being reviewed daily to comply with the latest government advice.”
The upgrade is Britain’s biggest road project and has employed a total of 13,000 people, with 2,500 working on the scheme at its peak.
Work was originally scheduled to be complete in time for the road to be opened to traffic by the end of this year, but it is now expected to be ready by the spring if there is no disruption.
Building started in November 2016 on the upgrade, designed to relieve congestion on the key freight link built more than 30 years ago to connect the M1 in the Midlands to the port of Felixstowe.
It carries around 85,000 vehicles a day, more than a quarter of which are lorries - well above the 10 per cent national average - and was renowned for delays caused by congestion and accidents.
The scheme involves upgrades to 21 miles of road between the Huntingdon and Cambridge areas, including the 12 mile long Huntingdon bypass which follows a completely new route to the west of the town between Lolworth and Ellington.
Preliminary work has started on the removal of the viaduct over Huntingdon railway station and the construction of associated new link roads in the town are also taking place, as the last major stage in the project with an expected opening date in 2022.