Hotel owners and local business groups have threatened to sue the city of Los Angeles if the City Council tomorrow approves a proposed hotel minimum wage mandate.

Speaking at a hastily arranged press conference on the steps of City Hall, chief executives from the city’s three leading business groups said the Council’s apparent rush to pass the $15.37 an hour minimum wage mandate violated promises the city made when enacting a wage mandate on airport-area hotels seven years ago.

Chief among the promises: that the city commission and review studies from three economists before expanding this higher wage to other hotels in the city or to other industries. The studies were released Monday, less than 48 hours before tomorrow’s scheduled council vote. The letter said labor leaders were exerting undue influence over the council to rush the vote before the studies can be properly analyzed.

“We are asking that the full City Council reschedule its vote on the wage mandate until it can carefully review the economic studies and for the public to be heard,” the business leaders said in a letter to the Council.

The letter was signed by Gary Toebben, chief executive of the Los Angeles Area Chamber of Commerce, Carol Schatz, chief executive of the Central City Association and Stuart Waldman, chief executive of the Valley Industry and Commerce Association.

The proposed ordinance would increase hourly wages for most hotel workers to $15.37, up from the current state minimum of $9. It would apply only to hotels in the city that have more than 125 rooms, and would take full effect in 2016.

The business leaders also submitted a letter from the Century City law firm of Loeb & Loeb that said if the Council approves the mandate tomorrow, it will have violated the process spelled out in the existing airport hotel minimum wage mandate and could prompt a legal challenge. Loeb & Loeb in the letter said it is representing the three business groups and two hotel groups: the California Hotel & Lodging Association and the Hotel Association of Los Angeles.

The Loeb & Loeb letter recommends that “in order to minimize the risk of legal action,” the Council should postpone its vote, hold a public hearing and have the ordinance spell out the legal basis for only applying to hotels with more than 125 rooms.