Balfour Beatty has won a £43.9M deal to upgrade a section of the A1.
The contractor will carry out the improvement scheme in Gateshead for the Highways Agency.
It will create a third lane in both directions on a 6.4km section of the road from Coal House to Metro Centre.
Link roads will also be added between the Lobley Hill and Gateshead Quay junctions.
The A1 widening works will require the installation of reinforced earth and concrete walls as well as sheet piling.
Extensive traffic management plans will allow the installation to be carried out during the day, reducing the need for noise during the night.
Balfour Beatty Construction Services UK chief executive Nicholas Pollard said: “Originally built 40 years ago, this section of road is currently one of the more congested sections of road on the Highways Agency’s network.
“We are delighted to have been selected to carry out these essential improvement works, which will increase road user capacity by 30%, reduce congestion and support regeneration and development, helping to boost the local economy.”
Work is due to start on site in late summer, with completion in early 2016.