Even a Manchester passenger has been making the case for a Norwich to London rail upgrade, transport secretary Patrick McLouglin has revealed.

At a meeting in Westminster this evening, the cabinet minister told MPs and an enterprise boss that the case for an improved line had gone beyond the borders of East Anglia, after he had been stopped in the northern station and told the line needed investment.

But he stopped short of committing to the half a billion pound wishlist put forward by the rail taskforce in its business case for an upgrade the line.

New Anglia local enterprise partnership chairman Mark Pendlington and Norwich and Ipswich MPs Chloe Smith and Ben Gummer met the Department for Transport head to push the case, ahead of a meeting with Treasury officials tomorrow.

It comes after they published their dossier last week, which claims that a £476m investment would reap economic rewards of £4.5bn.

Mr Pendlington said Mr McLoughlin had not committed to the investment in the line, and he had not expected him to, but added: 'Clearly he has read the report and gets what we are saying. What we have to do is keep up the pressure with the evidence right up to the Autumn Statement.'

He added that they had to make the Government see it was a 'compelling case'.

Ms Smith, who is co-chairman of the Great Eastern Rail Campaign taskforce, said: 'Patrick McLouglin is one of the most straightforward people in politics and I know he will take this report seriously. He has committed Department for Transport resources to this already.'

She said the group had made sure he knew how important the report was to thousands of passengers in Norfolk, Suffolk and Essex.

In a statement Mr McLoughlin said: 'The Great Eastern Main Line Taskforce and the Norwich in 90 campaign are helping to shape the future of the railways. I know that Network Rail will be looking closely at these proposals for the next round of rail investment funding and we will be looking at how these could be included in the next East Anglia franchise which is due to start in 2016.

'I want to see every town and city served by a world class railway systems. That's why as part of our long term economic plan more than £38 billion will be spent over the next five years to introduce more trains and better services.'