The UK High Speed 2 (HS2) London-Birmingham rail link promoter has floated a contract to employ 19 contractors under a six-year services framework if the £17bn project moves forward.
HS2 is considering spending £350m on professional technical consultancy to develop the design of the project, which is expected to be submitted before UK parliament in 2013.
The consultancy services include between £160m and £200m for civil engineering and structural design, and environmental services - local environmental impact assessments - will account for £50m to £75m.
Railway systems design services are expected to cost between £25m and £45m, while between £15m to £30m is planned to be spent on land referencing services.
The winning firm will have the option to extend the framework duration if the project goes ahead to the implementation stage.
HS2 was set up by the UK Government in January 2009 to explore the feasibility of a new high-speed rail line between London and Birmingham, and to consider rail services linking London, northern England and Scotland.