The 17-acre (6.9-hectare) complex has corrected only 20 percent of the 866 violations found during an inspection by the city's Fire Department six months ago, the mayor told U.N. Secretary-General Ban Ki-Moon in an Oct. 30 letter.
Bloomberg said that despite regular meetings between the city and Under-Secretary-General for Management Alicia Barcena, "the results are not satisfactory because to a large extent these conditions continue to exist."
In a Nov.
The mayor outlined a number of steps and deadlines - set for early next year - that the 55-year-old complex must meet to protect the public's safety, including the installation of additional smoke detectors.
"It is the city's obligation to take all necessary steps to protect the safety of all who work and visit in the city," the mayor wrote.
If the U.N. fails to adhere to the deadlines, the city "will be forced to direct the cessation of all public school visits to the United Nations," Bloomberg added.
The U.N. headquarters complex overlooking the East River is slated to undergo a $1.9 billion (€1.3 billion) overhaul that is to be completed by 2013.