Work is being carried out on the old Cornerhouse building in Manchester city centre after officials warned it could 'potentially collapse'.
The council said contractors are currently working to stabilise walls inside the building on Whitworth Street West.
An inspection found the structure was 'found to be moving outside of approved levels', a Manchester City Council spokesperson added.
A contraflow system has been put in place on Whitworth Street West while Network Rail - who manage the building - carry out the works.
READ MORE: Government department to open new 'hub' in Manchester city centre creating up to 400 jobs
It runs from Oxford Street, near Oxford Road Station, to Gloucester Street.
At least two bus stops have also been closed off, affecting some Stagecoach and Go North West services.
The town hall said the works outside the building are due to be complete by Friday (February 18).
Pictures taken at the scene showed a large crack in one of the outer walls of the building.
A sign on the building said: 'Unstable floor in building - DANGER KEEP OUT'.
Cones have been placed on the road in the contraflow area.
The Cornerhouse - a former cinema - has been vacant since April 2015 when it moved to the HOME complex at First Street.
A Network Rail spokesperson said: "We thank people for their patience while we carry out work at the old Cornerhouse cinema near Oxford Road station.
"Following routine inspections, we found historic movement inside the building.
"The work means the pavement outside is closed until the end of this week.
"Work inside the building should be complete over the next four to six weeks.”
The M.E.N has contacted Transport for Greater Manchester for a comment.