HSBC is seeking temporary office space in the City of London to reunite 450 of its displaced staff while engineers try to decide whether its bombed Bishopsgate headquarters should be written off. A structural engineering firm has been commissioned to determine whether the building could be made safe enough for staff to return, but its investigations could take months. In the meantime, management has recognised the importance of getting all staff back working under the same roof. Since the bombing, staff have been squeezed into three other HSBC buildings around London. A further 150 staff will go ahead with plans to move to the group's new London headquarters at the Midland Montagu building in Lower Thames Street. The bank's London offices took the full force of last month's IRA bomb blast that killed one man and injured 44. A two-metre crater remains where the bomb exploded. Every window in the building was shattered and there was considerable damage to computers, furniture and files as the force of the explosion blew out lift shafts and collapsed ceilings. Some experts believe the structural damage was so bad the building may have to be demolished. Mr Robert Sherbin, a bank spokesman, said all options were possible, including redeveloping the site from scratch. The neighbouring NatWest Tower was also severely damaged in the explosion which was thought to have caused about GBP1 billion (about HK$11.9 billion) worth of damage to the area. All of Hongkong Bank's London operations are back operating smoothly, although there has been some loss of efficiency. The great majority of the paperwork lost in the blast had been duplicated on computer and was retrievable. Some computers and records have been retrieved from the rubble, but some papers were blown as far as eight kilometres across the capital. Lost records are being pieced together and some transactions are taking longer to complete than otherwise would have been the case. Mr Sherbin said the cost of the damage could not be assessed until the future of the building had been decided. The building was fully insured.