A major Heritage Lottery Fund bid is to be submitted to turn the oldest functioning civic building in Britain into a heritage and exhibition centre.
A campaign to raise £750,000 for The Guildhall project in Bury St Edmunds was launched in December.
A undisclosed HLF bid is due to be submitted within the next three months.
The grade I listed building dates back to at least the 13th century although there is some evidence that it may have been used even longer ago than that.
It was once used by the townsfolk of Bury to imprision the abbot, and has since served as a court, a library, banqueting hall, and a council meeting place.
The Guildhall also includes the only surving ops room of its type from World War Two.
Part of the project is to bring that room back to how it would have looked at the height of its operation at the beginning of the war.
Next Wednesday will see St Edmundsbury Borough Council who manage the building asked to back the HLF bid.
It is also being asked to agree to eventual transfer of its management and maintence role and to a Guildhall management company.
The work, once funded, is expected to take up to five years to complete, the council report said.
“The long term aim of the project is to make the Guildhall fully sustainable and financially independent,” it said.
The Scouts and Guides still use the Guildhall while the Theatre Royal use it for their rehearsals.
The project’s long term goal is to recognise the historical importance of the building and bring it back into use as a thriving heritage building, serving as both a museum and as a public venue.
The project will also create green spaces, sensory gardens and court yard areas.
Bury St Edmunds Heritage Trust and the Guildhall Feoffment Trust are behind the project.Visit www.buryguildhall.co.uk