Street artist Banksy's painting on the wall of a derelict prison should be preserved and become part of an arts hub, an MP has said.
The mural of an escaping prisoner - possibly resembling famous inmate Oscar Wilde - appeared on the walls of the disused Reading jail on Monday.
Matt Rodda, MP for Reading East, said the artwork could become "an attraction in its own right".
The Ministry of Justice said it was considering what to do with the piece.
Banksy confirmed the work was his through a video on his website.
The clip - entitled Create Escape - showed the piece being created under the cover of darkness, set to archive commentary from American painter Bob Ross.
A man was spotted apparently helping to install the artwork the day before it was revealed.
Phil Tower, who was walking in the area on Sunday afternoon, said he took a picture after being intrigued by what was happening at the jail.
"It was the fact it was outside a prison that seemed a bit suspect," he said.
"I had not thought of it being graffiti - it was just one guy by the scaffolding.
"I don't know if that was Banksy or someone he got to put up the scaffolding for him - I'm not sure."
Another resident, Louise Urwin, said she rode her bicycle past the scaffolding twice on Sunday night after seeing "suspicious" activity and a woman in a high-visibility jacket keeping watch.
"I wish I'd looked under the tarpaulin now," she added.
Banksy's identity has remained a mystery since he began spray-painting trains and walls in his home city of Bristol in the 1990s.
Labour MP Mr Rodda told the BBC the painting had "caused real excitement in Reading".
"I hope that it can be preserved and that this part of wall will become an attraction in its own right, as part of the gaol becoming an arts and heritage hub," he said.
A campaign to turn the site into an arts complex has previously received backing from Hollywood actors including Sir Kenneth Branagh, Natalie Dormer and Dame Judi Dench.
Reading Borough Council said Banksy's involvement suggested he was backing the campaign to save the prison.
The Ministry of Justice said it was "considering next steps" regarding the artwork which it previously described as "graffiti".
Reading prison famously housed Irish writer Wilde between 1895 and 1897 and was immortalised by his poem Ballad of Reading Gaol, which reflected on the brutality of the Victorian penal system.
He was sent to the prison after being convicted of gross indecency for having an affair with Lord Alfred Douglas.