TOKYO, May 15 (Reuters) - A key member of a group of Japanese lawmakers aiming to legalise casinos said on Friday he was working hard to start debate on a bill in parliament this month, but he stopped short of guaranteeing its passage during the current session ending in June.

Takeshi Iwaya, a casino proponent and member of the ruling Liberal Democratic Party, told a gathering of gaming executives in Tokyo that he was still working to gain the support of lawmakers from the New Komeito and Democratic Party.

(Reporting by Nathan Layne; Editing by Chris Gallagher)