A demolition crew are today expected to carry out checks at the burned out Peacocks shop in Sunderland city centre.
Equipment arrived on site yesterday ahead of efforts to clear the site, which was devastated by the blaze on the night of Wednesday, January 23.
Blandford Street fire: Shocking pictures show damage caused by huge blaze in Sunderland city centre
It had been thought work would begin today, but it has now emerged investigations must be carried out to decide whether a partial demolition can begin.
The cause of the fire has yet to be confirmed, but it is not thought to have been suspicious.
Around 60 firefighters took a total of 10 hours to tackle the fire, with flames finally being extinguished at 5.20am on Thursday morning after they had been called to the scene at 7.20pm the night before.
A spokeswoman for Tyne and Wear Fire and Rescue Service said: "A demolition crew are on site at Blandford Street today to carry out an assessment of the building including whether to start partial demolition.
"They need to look at how to make the building safe.
"Once the building is made safe enough to enter the internal part of the fire investigation will be carried out by both ourselves and the private fire investigators, who are acting on behalf of the building owners and occupiers.
"Firefighters who tackled the blaze have been interviewed by the private fire investigators as part of the investigation.
"Once the building is deemed safer the cordon that is in place can be retracted."
A pathway on the main street has been opened up to allow people on foot to reach each end of the street.
People had been using the back lane while the barriers were still fully in place.