The rejection of the 69-mile route prepared over the past 15 months by Union Railways, a BR subsidiary, is being caused by the choice of route through London. The Union Railways report seeks to take the link through Islington and Hackney on the route of the North London Line, which will cause major disruption to existing passenger and freight services for several years.
The board is also worried about the legal implications of Union Railways' suggested route, which is the fifth to have been drawn up since 1974.
This new route going through east London was drawn up after the Government rejected the previous favoured route through south London. The original concept was for a 7-kilometre (4.3- mile) tunnel between Stratford in east London and King's Cross, but Union Railways' remit was also to attempt to bring down the cost of the route, originally estimated to be about pounds 4.5bn.
But while using the North London Line is likely to be cheaper, it will mean that the below ground station necessitated by the tunnel route from Stratford would no longer be feasible because the line would be coming from the north at a raised level rather than under the ground from the south.
However, London Regeneration Consortium, the chosen developers for the massive 150-acre largely derelict site north of King's Cross, would object to the cancellation of the station and the requirement to use part of the land for new overground tracks.
The solicitor advising the board has told its members that pounds 40m compensation might have to be paid and the board has advised Union Railways that it is not willing to face such a legal challenge and wants a route which fits in with its existing legal requirements set out in its deal with LRC.
One option being put forward by Union Railways is to avoid having to build any new station by routing trains to the much-underused St Pancras station next to King's Cross. The board has told Union Railways to resubmit its report by 14 January. The board was to have submitted the report on the rail link to the Government by the end of the year, with the hope that a route would be published sometime in the spring. This is now likely to be delayed.
Another problem with using the North London Line is the extensive disruption likely to be caused. While some of the route could easily accommodate extra track, there are pinch points in Hackney and eastwards towards Stratford where it will be difficult to build the new link. While the North London Line, which will have to be closed for up to five years, is not a heavily used commuter route, the main problem for existing traffic is for freight. The line is currently used to transport goods between East Anglia and the rest of Britain.
Last night, a spokesman for the board confirmed that there would be a delay in sending the report on the route of the link to the Government.