Education minister Ryu Shionoya said Tuesday that the Japan Teachers Union (Nikkyoso) should cooperate with the ministry on improving education, dismissing critical remarks by short-lived transport minister Nariaki Nakayama, who resigned Sunday after attacking the union and calling it "a cancer."

"Those comments totally miss the point," the new minister of education, culture, sports, science and technology said at a news conference. "It's very regrettable that a minister had to quit that way."

Shionoya, 58, said there was no relationship between Nikkyoso and the results of the back-to-back national achievement exams that were held last year and this year for the first time in 43 years.