Rail passengers should be offered automatic compensation if their trains are cancelled, a former minister has said.
Labour's Chris Bryant (Rhondda) called for the Government to simplify the process of claiming a refund for commuters who face disruption to their journey by widening it to apply to all passengers.
However Transport Minister Paul Maynard said the move would be difficult to implement as passengers would need to prove they were on the affected train.
The comments came after the Commons Transport Committee heard rail operators were "making money from delays" by failing to pay out millions of pounds of unclaimed compensation they received from Network Rail for unplanned disruption.
Mr Bryant, speaking during transport questions, told MPs: "It is so often that the school run train in Rhondda is cancelled or for that matter First Great Western Trains from London to Cardiff, and there is no automatic compensation on either of those lines which other providers do give.
"Why can't we have automatic compensation when a train is cancelled?"
Mr Maynard replied: "We need to ensure that whenever a passenger makes a claim for compensation they can demonstrate that they were on the train in question.
"Automatic compensation can be achieved if you have either a season ticket or an advanced purchase ticket."
Tory Martin Vickers, who sits on the transport committee, raised the issue of unpaid compensation after Department for Transport and Network Rail figures showed train operators paid out £45 million to delayed passengers in England and Wales during 2015/16 while receiving £105 million from Network Rail for unplanned disruption.
The Cleethorpes MP said: "One aspect of the ticketing system and the compensation is a lot of the money paid by Network Rail to the rail companies does not actually reach the passengers, which is quite scandalous.
"What action are you taking to ensure that money does actually end up in the passenger's bank account?"
In reply, Mr Maynard said the rail regulator was examining how to make the compensation payments process more transparent.