Proposals to force rail passengers from across England to change trains at Birmingham New Street have been branded "absurd" at the Conservative annual conference.

Shadow Transport Secretary Chris Grayling slammed the plans after delegates at a conference fringe meeting heard Chris Gibb, managing director of Virgin Cross Country, confirm that long-distance services might terminate at Birmingham in future.

The proposals would add to overcrowding at New Street, which is already so bad that Network Rail, the station's owners, has been forced to close it on occasion for health and safety reasons.

Services currently run from the south west of England, starting at Penzance, passing through Birmingham to the North-west, stopping at Crewe and Preston and continuing to Dundee in Scotland.

The line plays a crucial role in Britain's rail system because it allows commuters travelling from one end of the country to the other to avoid passing through London.

But under proposals published by the Department for Transport, services will terminate at Birmingham and passengers who need to continue their journey will have to change trains at New Street station.

Mr Grayling said the proposals would caused particular inconvenience to elderly travellers or those with heavy luggage, and add to the strain on New Street.

He said: "It will mean more people hanging around in New Street station making their connection when the station is already overcrowded.

"It is a bizarre indictment of the Government's failure over transport.

"Cross Country train services are going to be split in half. It all appears to be a result of the Government's failure to get to grips with the capacity improvements which are needed.

"My idea of improving commuter routes is not cop-ping Cross Country trains in half.

"What is ridiculous is that this is a decision taken by the Government. Why should Ministers be deciding whether we get through services or not, when it is something the train operators themselves can decide?"

Chris Gibb, managing director of Virgin Cross Country, said: "The Department for Transport is currently carrying out a consultation on the Cross Country network.

"They have proposed that on a journey like that, you will have to change at New Street.

"We await the results of that consultation. They have their own reasons stated in the consultation for that change."

The New Cross Country franchise is due to commence on 11 November 2007. It combines the current Cross Country franchise, which serves 20 million passengers a year, with parts of the current Central Trains franchise.

Virgin is one of four operators bidding to operate the franchise.

A Department for Transport spokeswoman said: "Our proposals for the new franchises will mean more services where passenger numbers have grown. We want to add new Birmingham to Northampton hourly services and give a more regular timetable from Birmingham to Cross Country destinations including a new hourly Manchester to Bristol service which will run via Birmingham.

"We have proposed that some passengers, those travelling between Devon and Cornwall and the north west, will have to change trains.

"For some, it may be easier to change at Wolverhampton or Cheltenham Spa, and same platform changes will be possible.

"We also expect bidders to let us know how they will assist those changing trains at Birmingham New Street."