Shortlisted construction companies have been invited to bid for the £1.9 billion contracts to build the roads, bridges, parks and woodlands of the Lower Thames Crossing project.

The proposed crossing, set to cost £8.2bn in total, includes the longest road tunnel in the UK and 23kms of roads that would almost double road capacity across the River Thames east of London.

The new route between Gravesend and Essex aims to ease congestion on the Dartford Crossing, improve journeys, and unlock economic growth by better connecting people to jobs and the region’s key ports, distribution hubs and manufacturing centres.

The £1.9 billion investment covers two contracts – one for roads north of the Thames in Essex and a second for roads south of the river in Kent. This is in addition to a third contract, worth a further £2.1 billion, to build the tunnels themselves and the approach roads, which will be tendered in the coming weeks.

The £600 million 'Kent Roads' contract includes 6km of new road, a junction with the A2, three green bridges, 20km of pathways and a new park near Gravesend.

The shortlisted bidders are: BFV JV comprising of BAM Nuttall Limited, Ferrovial Construction and VINCI Construction Grands Projects; Costain Limited; Kier Eiffage; and Skanska Construction UK.

The £1.3 billion ''Roads North of the Thames' contract includes 16km of new road, more than 30 structures including four green bridges and viaducts, and junctions with the A13 and M25, 40km of paths and new parks and woodlands.

The shortlisted bidders are: Balfour Beatty Civil Engineering and Kier Eiffage.

The contracts are expected to be awarded in summer 2023.

National Highways plans to submit an application for a Development Consent Order for the new crossing later this year, once it has held a further round of consultation which begins on May 12 .

In February the project was designated a "pathfinder project" to explore carbon neutral construction. It will work with everyone from engineering companies to universities to develop "innovative ways of building and maintaining low carbon infrastructure".

Katharina Ferguson, programme procurement director, said: "Our roads are at the heart of our way of life, and will continue to be long into our low-carbon future.

"The Lower Thames Crossing will improve journeys for millions of people, create opportunities for local people and businesses, as well as help the country on the road to net zero.

"We know the construction industry shares our ambitions, and I am incredibly excited to see how we can work together to set a new bar for low carbon construction and maximise the benefits to the local community."