Japan lags many other countries when it comes to efforts to fight smoking, with attempts to tackle tobacco often stymied by pro-smoking politicians, restaurateurs and Japan Tobacco, which is one-third government owned.
Yoichi Anami, a ruling party member of parliament, shouted "enough already" during a hearing last week when Kazuo Hasegawa, a 47-year-old non-smoker with stage four lung cancer, was testifying about the danger of second-hand smoke.
Anami's jeer sparked widespread criticism on social media and on Thursday, he issued a statement to say he was sorry if he had caused any "unpleasant feelings".
"I just murmured my feelings that smokers should not be discriminated against more than necessary," he said in the statement on his website.
Members of parliament were discussing a bill to limit passive smoking in public areas ahead of the 2020 Summer Olympics in Tokyo.
The law will allow smoking at a larger number of places than the original proposal had aimed for.
Smoking is banned inside schools and hospitals but most of them have outdoor smoking spaces.
(Reporting by Elaine Lies; Editing by Robert Birsel)
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