Victorian Britain led the world in the development of the railways but subsequently the network fell victim to Dr Beeching's axe and later privatisation – a sad contrast with the heyday of Stephenson and Brunel. In the last five years however passenger numbers have risen 40 per cent and freight 60 per cent. With the urgent need to tackle climate change by discouraging people from domestic flights the case for investment in high speed rail seems strong.

I am a longstanding campaigner for high speed rail and was greatly encouraged by the last government's announcement in March of a new line from London to Birmingham as the first phase of a network leading to Manchester, Leeds and thereafter to Glasgow and Edinburgh. Construction was to start in 2017 and during the election all three main parties committed themselves to backing high speed rail. The new government reaffirmed its support in the coalition agreement but with the cost of the original plan projected to be met largely from public funds a large question mark hangs over it if the current government makes the big cuts in infrastructure investment which it threatens to do.

Nevertheless, we need to look to the long-term - research shows that high speed rail could add up to £20bn to that of Scotland alone so that in the long term the project would generate its own income stream.

There is a very strong case for the line to extend to Scotland in order to increase business and tourist passengers travelling not just to and from London but also the North of England so that the UK benefits from prosperity spreading to a much greater degree outside the South East. The greatest benefits from high speed rail are also likely to be reaped where the reduction in journey times are greatest. I believe, therefore, that the government should give a definite commitment that the high speed rail line will extend to the North of England and Scotland.

The argument for high speed rail isn’t purely economic however. Transport also accounts for over 20 per cent of UK carbon emissions and if we are serious in reducing emissions we have to encourage people to use trains rather than planes for domestic journeys within the UK. Rail can also often be the most convenient way to travel given city centre connections and the lack of bother with check-in and security even leaving aside the recent chaos due to volcanic ash.

I want to see what the coalition parties' commitments mean in practice. Whilst debate is dominated by talk of spending cuts at present, we should remember that this is a long-term project which will create its own income flow. The plans announced in March showed the same scale of ambition that other European countries like France and Germany have shown in developing their railways. I urge the new government to look beyond present financial constraints and show that kind of vision - more reminiscent of our Victorian forebears than the destructive privatisation that took place under the last Conservative government.