WBA flyweight champion Kazuto Ioka relinquished his belt Thursday, his father and gym president Kazunori Ioka announced.

The elder Ioka told a news conference his son had been scheduled to defend his title for the sixth time on Dec. 31, but he will not be ready because he has not been able to keep up his training after getting married earlier this year.

The 28-year-old boxer's future plans are undecided, his father said.

"If he is up for it, I am ready to train him any time," Kazunori Ioka said. "If he doesn't have the motivation, he has no choice but to retire. It's one or the other."

Kazuto Ioka, who conquered his third weight classes when he became the WBA flyweight champ in April 2015 and has matched Yoko Gushiken's Japan record of 14 world title bout wins, married singer Nana Tanimura in May.