Labour MP for Newport East, Jessica Morden, led a Westminster Hall debate on 23 June on tolls on the Severn Bridge.
New tolls on the bridge between England and Wales came into force at the start of the 2010.
It now costs £5.50 for cars and £16.40 for HGVs.
There has been a long campaign on both sides of the bridge to allow drivers to pay by card - rather than the current methods of cash or cheque.
However the Highways Agency say a change in UK legislation needed to enable card payments is not yet confirmed.
Tolls are only paid on drivers heading westbound, ie into Wales, which has caused anger amongst some local residents.
The debate has been initiated by the Labour MP for Newport East, Jessica Morden.