A transport union is stepping up its fight to stop a key London to Scotland rail franchise being re-privatised after revealing the public sector company currently running it is paying "massive sums" back to taxpayers.

The East Coast main line has been under the control of the Department for Transport since the previous private-sector operator National Express pulled out in 2009.

In 2007, another private company GNER also ceased its East Coast operation after its parent firm Sea Containers ran into financial difficulties.

But the Government has signalled its intention to return the line to the private sector and has shortlisted three bidders with a new franchise due to start next year.

Today, the RMT union said new figures out this week will show that Directly Operated Railways (DOR), the company running East Coast, paid £235 million to the Government in 2013/14 - an increase of 12% on 2012/13.

The RMT added that DOR will have "paid back £1 billion to the British people since it took over in 2009".

RMT acting general secretary Mick Cash said: "It is a national disgrace that the Government is continuing with its plans to bulldoze through the re-privatisation of the East Coast line, despite the latest figures showing it is handing massive sums back to the British people."