The Government is in danger of choosing a "sub-optimal" rail company to run the nationalised East Coast main line when it is brought back out of public ownership.

Frontrunners for the West Coast rail line have been told they will be blocked from bidding for the line on the other side of the country that was controversially nationalised last summer.

The East Coast network has been beset with problems since the late Nineties. Private operators have handed it back to the Department for Transport three times in the last decade.

"It is odd because you will end up with a sub-optimal company running the franchise," said one rail expert.

A decision on the new operators of the West Coast franchise, that runs from London to Scotland, is due to be announced between May and September this year. The final three parties vying to operate the network have been told that the winner will not be able to bid for the East Coast line.