Cheltenham Borough Council has said the authority had ordered the owner to carry out "urgent works" on the house.
They were designed to stop further deterioration of the listed building, make it weatherproof and stop the risk of falling render.
Mark Nelson, enforcement manager at the Borough Council, said removing any pieces would be classed as a criminal offence.
We have endeavoured to protect the Banksy as much as possible and to this end the notice required the owner to have due regard for the Banksy mural whilst works were being undertaken.
We were aware of loose render on that part of the building where this was situated but the extent and how far it would affect the mural was unknown until work progressed.
The owner has left pieces of the render with attached Banksy Spy Booth mural on it with the council whilst investigations are continuing.
We would advise anyone against removing any further pieces from the location as this may be classed as a criminal offence.
Until the investigation is complete we are unable to say what if any further action will be taken.
An MP has called for an urgent inquiry after a Banksy mural was torn down - as sources close to the owner claim it has been destroyed.Read the full story ›
The popular artist's repeatedly vandalised work was in Cheltenham, just a few miles away from GCHQ.Read the full story ›
Hopes that the elusive urban artist Banksy might be returning to Weston-super-Mare have been dashed after the council denied any such rumours.
The Bristol artist pulled in the crowds in August and September 2016 with his antidote to theme parks, Dismaland, which he built in the former Tropicana on the seafront.
A Facebook group has claimed that he would be returning to the same venue with Happyland - in contrast to the miserable set up which proved so popular with visitors of all ages.
But any speculation has been quashed by North Somerset Council which says lots of events are planned for the Tropicana over the summer but none of them are Banksy's
A SWAT van painted by Banksy could fetch up to £300,000 at auction.
The second hand van has distinctive graffiti stencils and mysteriously disappeared after it was the centrepiece of the Bristol artist's debut US show in 2006.
It depicts heavily armed Special Forces agents being hoodwinked by a small boy on one side, while Dorothy from The Wizard of Oz amidst a sea of graffiti tags is on the other.
It was shown in an industrial warehouse in downtown Los Angeles as part of the show which also featured a live elephant, painted red and gold.
The eccentric show was attended by A-list celebrities including Brad Pitt, Angelina Jolie, Cameron Diaz, Jude Law and Dennis Hopper and was credited with kickstarting his rise to international fame.
Previous work by the mysterious artist has sold for up to half a million pounds.
The van has now resurfaced and is to be auctioned at Bonhams with an estimate of £200,00 to £300,000.
All of Banksy is on show here: his bravado, his imagination, his technical prowess, his confidence and his willingness to put his head above the parapet and use truth as a weapon.
The auction takes place at New Bond Street on June 24.
Schoolchildren arrived back at their classroom to find this surprise decoration adorning the side of their building.Read the full story ›
Banksy celebrates 25 years of street art with a South Bank Sky Arts Award nomination for Dismaland.Read the full story ›
An art installation shown at Dismaland last summer is back in the West for art lovers to view. The installation is hidden inside a forty foot shipping container and offers the chance to look at a model village with a twist.
Peek inside and there's a handcrafted miniature town - showing scenes of destruction and chaos. The installation is by Jimmy Cauty and inside there is a fictitious town you can view through peep holes.
It is known as Aftermath Dislocation Principle. It was first shown at Banksy's Dismaland in Weston-super-Mare last summer. But now it's on a UK tour - kicking off at Bruton Art Factory.
Banksy's Dismaland "bemusement" park was hugely successful, with enormous demand for tickets. This is a chance for those who didn't get tickets to see a most thought-provoking piece of art.
Gallery Directory Suzanne Bisset told ITV News: "It's a massive coup for us to get it and we're really pleased. Lots of people couldn't get tickets to Dismaland or weren't able to get in for whatever reason, whereas here it's free to get in and everybody's welcome."
For the next few days visitors to Bruton will be able to get a surreal model village experience. It's hoped it will be inspiring for all who view it.
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Bristol artist Banksy has created a new artwork in London attacking the apparent use of tear gas on refugees in the Calais "Jungle".Read the full story ›