Toru Mihara, a professor at the Osaka University of Commerce who helped lawmakers draft the casino bill, told reporters the government should tackle the issue of problem gambling through counselling and other means, and not by imposing a ban.
Mihara's comments suggest the debate over the casino bill, which is currently in parliament, may be protracted with supporters unwilling to accept any measures that would reduce the number of potential gamblers.
Asked whether he thought casino gambling should be limited to foreigners, Mihara said: "It would be entirely out of the question.""I would estimate that about 80 percent of all visitors will be Japanese. The remainder will be foreigners," he said.
Prime Minister Shinzo Abe has identified casino resorts as a key feature of his economic growth plan. Lawmakers are currently discussing an initial bill to allow this form of gambling, and the debate could spill over into an extraordinary session of parliament expected to start in September.
If the initial bill passes, debate will move to a second bill on more detailed regulations, which proponents hope to pass next year. Any delays in the process could dampen the hopes of global casino firms keen to unlock a gaming market in time for the 2020 Tokyo Olympics.
Companies including Las Vegas Sands and Melco Crown Entertainment are vying to win the first licences to operate casinos in Japan, a market that brokerage CLSA estimates could generate annual revenue of US$40 billion.