Lib Dems 'would scrap Severn tolls,' if returned to power
Tolls on the Severn Bridges would be scrapped if the Liberal Democrats are in government after next year's general election, the party said.
More than 80,000 vehicles use the two crossings each day, with the cost ranging from £6.40 for cars to £19.20 for lorries.
The money is collected by a private company and the funds are used to pay the construction costs of the bridges.
But the party says the change would be a "huge boost" for the Welsh economy.
The Freight Transport Association (FTA), which represents businesses, delivery companies and supermarkets chains, said the tolls were an "an unfair burden" and should be scrapped.
The bridges - the M4 Second Severn crossing and the M48 Severn Bridge - are due to revert to public ownership by 2018, although the UK government estimates it may take another two years to clear outstanding debts.
The Liberal Democrats say they would scrap the tolls completely, rather than retain a small charge to cover maintenance costs.
They claim the annual cost to the Treasury of paying those costs directly from public funds would be £15m.
Kirsty Williams, leader of the Welsh Liberal Democrats said: "We are the only party that will scrap the unfair Severn Bridge tolls.
"This announcement will offer a huge boost to the Welsh economy and save the average commuter around £1,536 a year. It will help to build a strong economy and a fairer society.
"These tolls shouldn't be used as a money-maker by either the Welsh or UK government. Tolls are extremely rare in the UK, so I see no reason why people should be forced to pay to enter Wales."
Jenny Willott, MP for Cardiff Central and a member of the party's manifesto working group, said: "These tolls are a genuine strain on local businesses in my constituency."
A Welsh Government spokesperson said: "The Department of Transport and the Highway Agency are currently responsible for both crossings, including the level of the tolls.
"However, we have made it clear to the UK Government that we should have a say on future of the tolls after the end of the current concession agreement with Severn River Crossing PLC."
The prospect of the tolls being scrapped was welcomed by businesses.
A Department for Transport spokesman said: "No decisions have been taken on the future management or tolling arrangements of the crossings after the end of the current concession.
"However, the government has been clear that any future arrangements will need to make proper provision for repayment of Government costs, future maintenance and reflect the needs of road users in both England and Wales."
Denise Lovering, chair of FTA's Welsh freight council, said: "The tolls are a major factor in the lack of regional distribution centres in Wales.
"And when you find out that the cost to some companies is in excess of £500,000 a year it doesn't take much to understand what a boost to the economy the removal of the tolls would be."
FSB Wales spokesman Rhodri Evans said: "We believe that the tolls must be reduced as soon as the bridges pass into public ownership and welcome any commitment to do so."