Bristol couple Rod and Joanne Hartrey have lodged a complaint against a leading councillor in a row over a strip of land next to their home.

They claim Liberal Democrat cabinet member Gary Hopkins told others they wanted to build on the council-owned land in Knowle and watched them from a neighbour's property as they cleared part of the site.

Mr Hopkins denies the claims but the council's Standards Committee has launched an investigation.

The couple said there had been problems with the patch of land for several years which measures 60 feet by 20 feet and had become badly overgrown.

They cleared the site, next to the entrance to Redcatch Park, after being given a gardening licence in January by the council.

Mr Hartrey, aged 40, said after Mr Hopkins became involved they were told to stop any work on the land.

He said it had previously been used as a council compound, where a large steel container and a skip were kept.

The skip was used for dog waste bags which were found in the park but people also used it for dumping their own rubbish. The compound was also used for storing car body parts and other items which were found in the park.

Self-employed builder Mr Hartrey said the land was a haven for drug users and caused anti-social behaviour at night.

He said it became so overgrown that full-grown trees blew over in gales – one of which demolished his garden shed.

The overgrowth eventually damaged their fence which led to a meeting at the site – which has no public access – with council officials.

Mrs Hartrey, 39, an office worker, said this led to the council suggesting a garden licence as a solution to looking after the land and keeping it tidy.

She said: "All we've ever wanted to do is to secure the site and keep it tidy."

But the couple said that Mr Hopkins became involved when Mr Hartrey hired a machine to remove some large trees and their stumps which were diseased and put their property at risk.

Mrs Hartrey said they had been told Mr Hopkins was watching them from a neighbour's property.

She claimed: "That was on the weekend and on the Monday, he went to the council's parks department to find out what we were doing and whether we had permission. He didn't come and knock on our door and ask us for an explanation."

They claim that Mr Hopkins told people that the couple wanted the strip of land for building purposes.

Mr Hartrey said: "We've never had any wish to do anything else except clear up the piece of land which has no public access and safeguard our own property."

The couple said they were given a choice by the council to either end the garden licence or agree to a consultation with residents over a licence being issued.

They agreed to consultation but said they now did not think they would secure a garden licence.

Mrs Hartrey said: "Everything we've done has been above board and with the best of intentions."

Mr Hartrey said: "Because I'm a builder, people have been putting two and two together and coming up with something which is not true. We don't want to build on the land."

Mr Hopkins, who rejects the claims against him, said he never saw the couple except on the day that they turned up at his house and angrily complained to him. He said he had not made derogatory remarks about them to others.

He said the only reason he contacted the parks department was because of the complaints that had been made to him about the lack of consultation over the garden licence being granted in the first place.

The issue will go before a hearing of the Standards Committee some time next month. If the decision goes against Mr Hopkins, then the committee has powers to impose a range of sanctions from a written reprimand to suspension of duties, which would lead to a loss of the councillor's annual allowance.

Mr Hopkins is Cabinet councillor in charge of the council's environment and community safety department. It is possible if he challenges and wins the leadership of the Lib Dems after the local elections in June, that he could become the next council leader.