The National Audit Office says pressures put on train operators by the Government to maximise cash coming in from travellers mean fares will continue to rise above inflation.

Last year's fare increases by Virgin, which operates the West Coast Main Line franchise, Northern Rail and TransPennine Express made some journeys more expensive per mile than flying abroad.

It is expected regulated fares – including season tickets and walk-on tickets – will go up by an average of 5.1% in January.

Today transport campaigners said further increases would be unacceptable.

Aiden Turner Bishop of the Campaign for Better Transport in Lancashire said: "If the price of oil is going down why are the train fares not going down?

"If we can intervene in banks for public reasons why can we not intervene in trains and infrastructure?"

The NAO report also states that overcrowding is an "increasing problem".

But the Department for Transport has been unable to say where and when an extra 1,300 carriages will be introduced, only that they will all be in place by 2014.

Anthony Smith, chief executive of train watchdogs Passenger Focus, said passengers will find yet more increases "difficult to understand when they already question their train ticket's value for money".

Rail users told the Evening Post they think fare prices compare favourably with the cost of travelling by car – so long as they have room to sit down.

Andy Tatchell, who works at the postal workers union on Garstang Road, said: "I think fares are OK in general apart from some parts of the day.

"I tend to go in the middle of the day simply because £250 to go down to London from Preston is just not on really."

Hospital worker Sandra Shaw, 45, who comes to Preston from Barrow to go shopping, said: "It's still cheaper than coming by car. It's easier but it was crowded coming down, they didn't have enough coaches on."

Graham Chisnall, 37, who was travelling home to Southport, said: "I don't mind as long as they put more carriages on, because it's so annoying when you're paying £25 to £30 for a train ticket and you've got to stand up."

Phil Parr-Burman, 47, on his way home to Edinburgh, said: "They're all right. We paid £20 return from Edinburgh. We don't do that much train travel so it's not going to hit us hard."

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