The Office of Rail Regulation last month said it was ?minded? to allow a new train company, Grand Central, to run three trains a day between Sunderland and London, and it turned down a plan by GNER to run additional trains between Leeds and London.

Extra trains to and from Leeds are a key feature in GNER?s new 10-year franchise, which would net the government more than £1 billion in premium payments.

Now, according to the Yorkshire Post, ?in a highly unusual move? the Department for Transport (DfT) has written to the ORR to express concern over its decision.

Dr Mike Mitchell, DfT director general of rail, said: "We remain to be convinced that there is justification for the promotion of the benefits to Sunderland passengers above those of Leeds when the economic appraisal finds in favour of Leeds, and that this weighs more heavily than the needs of other passengers on the route who may find their trains retimed to accommodate the new services, or performing less well because of them."

The Yorkshire Post said he expressed concern about the impact of Grand Central's services on other companies with train franchises.

Dr Mitchell also criticised the ORR for not agreeing to a meeting to clarify issues, said the newspaper.

Grand Central said it would competitively grow the market, and Leeds was already well served.

The ORR declined to comment.