Traders at a Norfolk market town have been urged to dig deeper in their pockets to ensure that car parking remains free of charge.

Harleston was the only community in South Norfolk to stand up against proposed pay and display charges four years ago and opted to pay to keep them free for shoppers and businesses.

However, town councillors have warned that local shopkeepers and businesses will need to contribute more in future as officers investigate the viability of renewing the lease of the town's car parks from South Norfolk Council next year.

Harleston Town Council entered an agreement in 2008 to adopt the district council's sites in Broad Street and Bullock Fair Close at a cost of �20,000 a year to save the town from parking charges.

But there are fears that the town council could be left to fork out even more when the lease is up for renewal next October and the cost could go up more than 5pc in line with the Retail Price Index (RPI).

Roger Plant, chairman of Harleston Town Council, said the council would be looking to approach a handful of traders to form a committee to help boost business contributions towards parking. He added that other services would suffer if the council had to pay more for a car park lease without extra financial help.

'Residents are unaware how costly a business it is to run a free car park. The town council can not afford free car parking and someone has to contribute some money elsewhere. The money is finite and car parking costs get more and more expensive.'

'If Harleston does not renew the lease of the car parks I guess South Norfolk Council will take it back and put a pay and display machine there tomorrow,' he said.

Ian Carstairs, chairman of the Harleston Have Your Say group, told town councillors on Wednesday night that a town survey published last year said that 90pc of respondents felt it was important to keep parking in Harleston free.

But councillor Adrian Brownsea said that the 90pc were not aware that the council was paying most of the costs.

'Without doubt the decision [to keep parking free] was influenced by a loosely organised committee of traders in the town voicing an opinion that they would share the costs 50/50 and they have not by a long chalk in any way and there is no willingness to do it,' he said.

Margot Harbour, town clerk, said a 'fair proportion' of businesses did contribute to parking.

Councillors agreed to investigate future costs and the possibility of getting more trader support before making a decision in the New Year.

Off-street pay and display charges are in place in the other South Norfolk market towns of Diss, Loddon and Wymondham where the first hour is free.