The biggest part of the work will cover the package of structural and civil engineering design, which is expected to be worth up to £200m.

This is being broken down into five main packages,including design for Euston station, the London metropolitan section, southern rural and northern rural sections, and the route into Birmingham.

Over all the project offers a much-needed work boost to the shortlisted firms, which will now eagerly await the first individual work packages.

The first of these will flow through when CH2M Hill takes up its role as project promoter later this month.

The framework has been split up into four disciplines: