An area occupied by a disused part of Nottingham prison could be reused to help relieve overcrowding, the BBC has been told.
Twenty police cells in England are set to take prisoners as the jail population reaches its maximum.
The Home Office has confirmed it is looking at other plans, including using the land where B-wing stands, which has accommodated 250 inmates previously.
The Prison Officers' Association (POA) has expressed surprise at the proposal.
The wing is empty after being closed in October 2005 after new accommodation was built at the jail.
Demolition put forward
A Home Office spokeswoman said: "We are not planning to reopen the wing but make use of the space the wing occupies."
She said the plans were at an early stage and no details had been decided.
It is understood that demolition of the wing is one proposal being considered.
A report from the Independent Monitoring Board said the wing should be demolished.
Paul Easom, the POA branch secretary at Nottingham prison, said: "The plans that we've got on the table at the moment are for a complete refurbishment which means knocking down the whole of the Victorian side of the prison."
An added problem was the lack of prison officers to run a new unit, he said.
"You would be looking at six months at least to recruit and train them," he said.
Chief Inspector of Prisons Ann Owers said she had inspected B-wing and found it was not fit to be used.
"It's not just about providing prison cells - it's about providing work, activities and education for the men and women who are in those cells to try to make sure they get the skills they're going to need when they leave prison," she added.