Three groups have been shortlisted by the Highways Agency to widen 63 miles of the M25

Three groups have been shortlisted by the Highways Agency for the £5bn project to widen 63 miles of the M25.

The shortlisted firms are made up of three groups: Amey, Laing O'Rourke and Ferrovial Agroman; Connect Plus (Balfour Beatty, Skanska, Atkins Ltd and Egis Projects SA); and Flow (Vinci, Autoroutes Du Sud De La France, Laing Roads Ltd, Carillion, Costain, Ringway, Mouchel Parkman, Norwest Holst and Jacobs).

Final tendering will take place in early 2007, with the contract to be awarded in 2008.

The new lanes are expected to help improve traffic flows on the M25, which is one of the world's busiest roads. The contractor will also be required to keep the motorway and its structures in good condition over a 30-year period.

Delivery of the widening will be co-ordinated with other improvements in traffic management to lock-in the benefits of widening, such as the introduction of variable speed limits to smooth traffic flows in busy periods.

It is expected that widening works will be suspended while the 2012 Olympic Games are underway.