A "six-figure" deal to keep a Banksy mural which targets the issue of Government surveillance at its current site is nearly complete, an art dealer has claimed.
Robin Barton, from London art gallery Bankrobber, said he was approached by the owner of the Grade II listed building, on which the Spy Booth artwork is painted, after he was "shocked at the level of vitriol" following reports that the piece may be sold and removed.
The creation shows three 1950s-style agents, wearing brown trench coats and trilby hats, using devices to tap into conversations at a telephone box.
It appeared overnight on a street in Cheltenham, Gloucestershire in April, just a few miles from GCHQ, where the UK's surveillance network is based.
Scaffolding erected around the artwork on Wednesday was initially believed to be for maintenance work.
But John Joyce, of Q Scaffolding, later claimed his boss, street art collector Sky Grimes, had bought the piece from the property's owner and planned to remove it.
Mr Barton said the building owner had since contacted him, claiming he had received death threats amid widespread local opposition to the reported removal plans.
The art dealer said a six-figure deal was now near completion with the "local business community" that would ensure the work remains at the site.
There were also early discussions about converting the building into a Banksy museum, Mr Barton claimed.
"A deal is close to being concluded that will see this much loved local landmark remain in situ and protected into the future," he said.
"Pending no disasters, as far as I'm concerned the deal will go through and the piece will remain where it is."
Banksy officially confirmed the piece was his work on a link titled Q&A on his website.
Local residents and business groups in Cheltenham say the removal of the artwork would be a "huge loss" to the spa town.
Michael Ratcliffe, chief executive of Cheltenham Chamber of Commerce, said: "It has been a great asset, a lot of people have been coming to the town to see it.
"If we can keep it in the town we will - we want to keep it in the town."
A spokeswoman for Cheltenham Borough Council said the owner was not required to inform the authority what was happening to the piece.