Network Rail, the company set to take over Railtrack's operations, has been branded "unaccountable, introverted and deeply flawed" by a think-tank review.

Network Rail will be less accountable than Enron and Worldcom ever were

Ed Mayo, NEF director

The criticisms were published by the New Economics Foundation (NEF) which claims the new non-profit model is too bureaucratic.

Network Rail, which is acquiring Railtrack for �500m, retaliated by saying the report was "ill-informed criticism".

It is expected to take over the running of tracks, signals and stations next month.

'Less accountable than Enron'

The NEF's key objection is that the management board of Network Rail can veto the nomination of potential 'members' or governors.

This body of people, claims the NEF, should be there to hold the company to account. But if only those allied to the board are ever nominated, it says this will prevent a democratic board structure.

"This is a missed opportunity to turn the widespread anger and frustration with Railtrack into goodwill," said NEF director Ed Mayo.

The NEF wants more staff, regular passengers and local voluntary rail groups to be involved in the running of the railways.

Mr Mayo warned the current model for Network rail means it will be "less accountable than Enron and Worldcom ever were".

'Ill-informed'

Network Rail has outlined its intention to have a board made up of six executives and seven non-executive directors.

It says the company will answer to rail industry members and representatives of passenger groups.

A spokesman for the group said:" The board will be held strongly into account by well-informed and active members".

Network Rail says an independent membership committee will put forward candidates for election and that claims of unaccountability are "ill-informed".

The NEF based its review on a report by a senior associate, Dr Johnston Birchall, a senior lecturer on social policy at Stirling University.

The group is researching other non-profit organisations and advising the government on the design of new non-profit NHS 'super hospitals', or 'foundation trusts'.