A survey carried out by the CBI has revealed that high street retailers are experiencing the worst slump in sales in quarter of a century. More than 60% of respondents said sales were down in the first half of July – over twice the number (25%) who reported higher sales.

Although the impact of the credit crunch on consumer spending has been cited as a major factor, in addition to soaring food and fuel prices, the FPB believes that parking charges are causing shoppers to reject high street shops in favour of large, out-of-town retailers providing free, on-site parking.

"Access is a major component in determining the future of our town and city centres. More taxes on motorists mean that high street shops are less able to compete for trade against the larger retailers," said the FPB's Policy Representative, Matt Goodman. "The damage caused by various parking charges is done to the community as a whole, because more money is taken out of the pockets of both consumers and local businesses."

In addition to fighting existing parking restrictions, the FPB is opposing a proposed scheme in Nottingham to charge some firms an annual fee of £185 for every car parking space they provide for employees. There are fears from some of the FPB's members that this could be introduced elsewhere in the UK.

In many towns and cities, motorists can only park for short periods or face large fines. The Traffic Management Act 2004, which came into force on 31 March 2008, transferred Civil Parking Enforcement (CPE) powers to levy parking charges from the police to local authorities. Currently, more than 350 councils wield these powers. Although guidelines on the Act say that it should not be used simply to raise revenue, in practice, this is often difficult to monitor.

FPB member and art dealer Omar Ashlan owns Amador, a shop in Knutsford, Cheshire, which is located in the Borough of Macclesfield. He believes the town has seen a sharp increase in the number of penalty notices being issued to motorists for contravening waiting times since the Act came into force.

"It has become a lot worse recently – my sales have gone down by 25% since the Council took over the enforcement of parking," said Mr Ashlan. "I've had people rushing past my shop saying they would love to come in, but are worried they will get a ticket if they are a minute late. It's creating a culture where customers are scared away because they stand a good chance of having to pay out."

He added: "This is not helping trade to flourish, especially in the current economic downturn. It's a way for the Council to rake in more money while stopping people enjoying the experience of shopping in a town like Knutsford."

In the nearby Borough of Congleton, the Council has historically elected not to impose any parking charges, fearing that trade would suffer.

"We've lost a lot of industry over the years and parking charges certainly stifle trade," said Gareth Evans, who is a member of Congleton Borough Council. "Instead, we have chosen to encourage trade by keeping parking free. It appears to have worked, with all the towns across the borough packed with shoppers, including quite a few who come from outside the area."

The Government has backed the findings of the Competition Commission's inquiry into the groceries market, which include calls for an ombudsman to oversee a strengthened grocery supply code of practice, and support for smaller suppliers in their dealings with larger retailers.

However, the FPB is concerned that some of the measures do not go far enough. Introducing a ‘competition test' in local planning decisions, for example, is likely to promote competition between rival supermarket chains instead of protecting smaller high street shops.

Small shops are disappearing at a rate of 2,000 every year. In the preliminary findings of the inquiry, announced in April, the Conservative Party's Parliamentary Enterprise Group repeated a warning, originally made in 2006 by the All-party Small Shops Group, that the majority of the UK's smaller retailers could disappear by 2015. Then FPB believes that parking charges are a major factor behind the slump in high street sales.