The UK highways Agency has awarded a £6.2bn Design Build Finance and Operate contract the M25 motorway.

The work to be carried out by private sector consortium Connect Plus includes widening of M25 to four lanes as well as renovation of Hatfield Tunnel.

In addition, the contract includes operation and maintenance of the M25 and the Dartford Crossing for 30 years.

Transport Minister Andrew Adonis said that the widening schemes, combined with the maintenance and operation of the M25 network for the next 30 years, will reduce congestion, improve journey time reliability and safety and benefit road users.

The construction work will be completed in phases before the start of the 2012 Olympics.