HS2 is considering selling spare data capacity from fibre-optic cables running alongside the in-construction railway project to local broadband providers in a bid to improve internet connectivity along the route.

The new railway – which will link London and Birmingham – runs through largely rural areas of Buckinghamshire, West Northamptonshire, Warwickshire and Staffordshire, many of which lag behind the rest of the UK in terms of data speed and mobile coverage.

Around 2,000km of fibre-optic cabling will run alongside the railway, as well as a series of telecoms masts, to support the railway’s signalling and telecoms and provide data to passengers.

On a typical train, mobile devices get their data from each telecoms mast the train passes – jumping from one to another in quick succession. This often leads to reduced bandwidth and occasional drop-outs.

On HS2 services, however, the data can also be fed directly to the train, which will then link onward to passenger’s phones, significantly...