Democratic Party of Japan leader Banri Kaieda remained circumspect Saturday over joining forces with Diet veteran — and former DPJ chief — Ichiro Ozawa's newly created Seikatsu no To (Lifestyle Party) prior to the Upper House election this summer.

"I have never said that I will cooperate with Ozawa," Kaieda said on a TV program aired by Tokyo Broadcasting System Television Inc.

"We can't afford to lose even one of our 57 lawmakers in the Lower House," he said, apparently referring to lingering hostility in his party's ranks toward Ozawa and his followers, who abandoned the then-ruling DPJ en masse last year in opposition to its planned sales tax hike.