The Public Works Department claims the Pathumwan District Office ignored its warnings to stop construction of the 24-floor Aetas Bangkok Hotel which violated building regulations.
The department, which approved the hotel project that began in 2005, said it found later that Ruamrudee Road, which is less than 10 metres wide, is only allowed to accommodate an eight-floor building.
This resulted in the department issuing 12 warnings to the district office urging it to stop the construction.
But the office failed to follow the instruction, a source at the department said.
The source said the district office notified the hotel owner after the construction was almost complete.
Residents in Ruamrudee Road filed a complaint against city officials in 2008 for allowing the hotel to be built on a road which is less than 10 metres wide, breaching the 1979 Building Control Act.
On Tuesday, the Supreme Administrative Court ordered the Bangkok governor and chief of Pathumwan district to oversee the demolition of the hotel within 60 days.
The source said the department approved the plan only because the district office assured that Ruamrudee Road was wider than 10 metres.
This will be the toughest time for the district office, the source said, adding the hotel was likely to sue the district office as it allowed the hotel to be built. It could claim it was not aware of the order.
He said a committee will have to investigate the case.
Pathumwan District Office director Sittichai Thoumsakont said he didn't know about the warnings as he had only taken office a few months ago.
Mr Sittichai said the office had to follow the court instruction, but he was still waiting for the court order to arrive at the office.
Following the court order, deputy city clerk Krisada Klantanon was concerned that some of the other tall buildings on the road could breach the building regulation for the same reason.