Renewed calls have been made to scrap the Severn Bridge and Second Severn Crossing tolls on the day prices go up.
From Thursday, cars pay 10p more at £6.50, small goods vehicles and small buses face a 30p rise to £13.10 while heavy goods vehicles and buses will have to pay £19.60, up from £19.20.
Bridge owners Severn River Crossing PLC increase the cost every January in line with the Retail Price Index.
More than 25 million vehicles use the two bridges each year.
The money is collected by a private company and the funds are used to pay the construction costs of the bridges.
That debt is due to be cleared by 2018, when they revert to public ownership.
But the Liberal Democrats have vowed the get rid of the tolls if they are in government after the 2015 general election.
Welsh Liberal Democrat MP for Cardiff Central, Jenny Willott, said the south Wales economy would be boosted by £107m a year by scrapping tolls.
Severn crossing
Repeating the party's intention, she added: "Motorway tolls are not prevalent across the United Kingdom. So why on earth should people be forced to pay a tax to enter Wales?"
Meanwhile, Plaid Cymru called on the UK government to reveal what it plans to do with the bridges when they come back into public ownership, claiming there could be tolls for up to nine more years.
The party's Westminster transport spokesman, Jonathan Edwards, said: "While the crossings are likely to revert to public ownership by 2018, the UK government will still have the right to recoup its costs.
"This right lasts until 2027. Under current tolls it would take one to two years for the government to recoup its costs but at the moment it is deliberately keeping its intentions hidden."
The UK Highways Agency said owner Severn River Crossing is entitled to collect a defined sum from the tolls - £1,028.9m in July 1989 prices - which is due to be recouped by 2018.
A spokesman added: "After this time, the crossings will be handed back to the government. No decisions have been made regarding the future of the Severn bridges.
"From this point onwards, government has the right to recoup its own costs from the construction, maintenance and management of the bridge until 2027.
"This would be for costs that fall outside of the scope of the current concession for example costs incurred for cable corrosion work."
