Sajja Khontrong, chief of Wattana district, said an order was released Sunday informing the owner that the use of the building is prohibited until inspection of the damaged structure is concluded.
A team of certified engineers and experts will conduct the inspection. It is unclear when they will finish their work.
Mr Sajja said the 13-storey building, which rented space to 30 company offices, will be off-limits to unauthorised people.
He warned that violators of the ban face up to six months in jail and may be fined 30,000 baht.
A huge fire started on the seventh floor about 2.30pm on Saturday. It spread and consumed the upper floors as narrow streets and power lines impeded firefighters.
The blaze was brought under control two hours later.
No one was injured. The cause of the blaze has not been determined. Electrical wiring on the seventh floor was recently replaced, an initial police report said.
At 7.30am yesterday, the fire re-ignited on the ninth and eleventh floors. It was quickly extinguished.
The first official inspection team joined by the police, engineers and Thirachon Manomaipibul, deputy Bangkok governor for civil engineering, checked the damaged building yesterday.
Mr Thirachon said the impact of the fire on the building structure was minimal.
However, the floors were full of water from the dousing operation. Much of the interior was covered in ash.
The fire had spread rapidly partly because the glass interior had tinted films on them, which were inflammable.
The 33-year-old Fico Place was constructed before the Building Safety Control Act 1992 was enacted requiring installation of adequate water sprinklers.
He said City Hall will survey older buildings in the city to see if they are equipped with the sprinkler system.
City Hall might draft legal requirements for every older building in Bangkok to make them comply with the 1992 act.
Pol Col Rattasak Raksalam, chief of Thong Lor police station, said the building owner and tenants will be called to give statements.
They will be asked to provide details of the damage to their property and offices.
Forensic scientists will establish the cause of the fire.
Theerathat Kongchan, director of human resources at Fico Place, said the building suffered substantial damage inside.
Documents about companies with offices in the building were lost in the fire.