The discounts available for travel on most railcards are set to be trimmed on 15 September, according to reports.

The effective rises in fares will be small, because the present discounts of 34 per cent are said to be coming down to 33.4 per cent, which is just over the ‘third off’ which is normally advertised.

The result would be that a fare of £100 would be reduced to £66.60 instead of £66 exactly.

The main exception would be the 16-17 Railcard, which would continue to offer a 50 per cent discount.

Although the rise amounts to 60p for every £100, transport campaigners are protesting.

Railcard, the organisation run by the Rail Delivery Group, said: ‘The cost of a Railcard hasn't increased for over 10 years and will continue to provide customers with a third off their rail fare for just £30 a year – a cost that can be made back in just one or two journeys.’

If the reduction in discounts does go ahead, it will not benefit train operators. The Treasury or the devolved governments already collect all the income from rail fares, while paying the industry’s costs and a management fee to those English operators which have not yet been nationalised by transferring them from a private sector company to DOHL – the Department for Transport’s operator of last resort.

The government’s Passenger Railway Services (Public Ownership) Bill, which would allow the remaining National Rail Contracts to be terminated at the next break point – usually the ‘core expiry date’ – is due to receive its Third Reading in the House of Commons tomorrow and be in force by the end of the year.