Bidders include Balfour Beatty, Carillion, Costain, Sir Robert McAlpine, Skanska and a BAM Nuttall/Morgan Sindall joint venture according to construction information specialist Glenigan.

The tender submission date set by the Highways Agency is March 5.

The scheme was one of a number of projects to receive the go-ahead from the Chancellor in his Autumn statement last November.

The main construction work is scheduled to start in Autumn 2013 but site clearance began in January this year.

Mike Hall, the agency’s project manager on the scheme, said: “Carrying out the site clearance now before the start of the spring bird nesting means we can avoid the presence of nests which might otherwise lead to a delay in the start of main construction.”

The scheme comprises widening a 4.6-km stretch of the A14 between junctions seven and nine with the inclusion of an extra lane in each direction to prevent congestion at the traffic black-spot