"The government cannot govern by referendum," Lee said, "The casino is not an issue of national survival or sovereignty that deserves to be settled by a referendum."
The possibility of a casino in Singapore has become a polemic issue, with many religious groups vehemently opposing it. An online petition against it has also drawn tens of thousands of signatures.
Singapore already has many forms of legal gambling.
Lee reiterated Singapore's Cabinet will decide the casino question in 4-6 weeks after careful examination of the proposals.