Graffiti artist Banksy said he is ‘surprised’ his work has been given Grade II listed status.

A row over the anonymous Bristolian’s piece erupted when he sprayed a spy booth mural on the wall of a Cheltenham home – just miles from the Government listening post, GCHQ.

The council was forced to step in and agreed the mural and a satellite dish incorporated into the design, should be protected as part of the listed building.

On his website, the artist was asked what he thought about his work gaining the status for the first time.

He replied: “It’s surprising because when I did art at school I got an ‘ungraded’.”

A listed building has special architectural or historic interest and there are around 500,000 in England.

The protection means it may not be demolished, extended, or altered without special permission from the local planning authority.

Banksy’s success means his once controversial graffiti is now so often overshadowed by ownership debacles.

The graffiti in Cheltenham appeared a year ago and the decision to have the work listed in February has effectively meant the owner of the home cannot sell it.

The community in the spa town had been campaigning to keep it amid fears it would be removed and sold.

Meanwhile in Gaza police have stepped in and seized a door bearing a Banksy drawing after its owner said he was tricked into selling it for less than 200 dollars (£135).

The mural of a Greek goddess was painted on what was left of the Dardouna family’s house after last year’s war.

A court is expected to have to resolve whether the family or the local artist he sold it to is the true owner.

Banksy himself had to sort out an argument after the Mobile Lovers appeared near Broad Plain Boys’ Club in Clement Street, Bristol in April.

It was painted on a piece of board stuck to a doorway on a council-owned property and a dispute between the council and the boys’ club started.

The street artist eventually wrote to the club to say they could do what they wanted with it and it was sold to a private collector for £403,000.

It is hard to believe the debate in 2006, when the Banksy picture of a bloke hanging from a sill while a lady in her skivvies and a man look out of the window, appeared in Park Street centred on vandalism or art. Councillors voted to keep it – in hindsight a good decision.

In 2009 when Banksy staged one of the most popular exhibitions ever to have been held at the City Museum Art Gallery, many realised there was money in our street art.

• -Listed buildings are given extra protection by planners when it comes to proposals, building work, alterations and developments.
• -In Bristol there are nearly 4,500 listed buildings spread across the city.
• -Grade I listed buildings are of exceptional interest and account for around 100 in the city.
• -Grade II* are particularly important buildings and account for about 500 properties in Bristol.
• -Grade II listed properties make up the remaining number. The listing means they are of special interest and are often private residential buildings.

Examples of other Grade II listed properties in Bristol include:

• -The ABC Cinema in Clifton also known as the Whiteladies Picture House, built before 1920 and 1921.
• -The Bristol Hippodrome in St Augustines Parade built by Frank Matcham in 1911.
• -Brown’s Restaurant, the former City Museum and Library and University Refectory in Queens Road.
• -The Kings Head Inn in Victoria Street.
• -The Trinity Road Library in Lawrence Hill that was built in 1896 and originally the St Philips public library.
• -Wills Hall in Stoke Bishop