Kazuto Ioka will defend his WBO super flyweight belt against Ryoji Fukunaga on New Year's Eve, a bout that will replace a planned fight against Jerwin Ancajas of the Philippines, organizers said Thursday.

The 115-pound unification clash between Ioka and Ancajas that was scheduled for Dec. 31 was postponed after the Japanese government enacted a tentative one-month ban on foreign travelers due to the threat of the COVID-19 omicron variant.

Instead, Ioka will face super flyweight champion Fukunaga in the New Year's Eve world title showdown at Ota City General Gymnasium.

"Not being able to have the unification bout on New Year's Eve is unfortunate," Ioka said in a comment released by Shisei Boxing Gym. "But now that this is decided, I want to win and build on that for my next fight."

The unification bout was supposed to be Ancajas's 10th title defense since capturing the IBF title in September 2016.

Ioka was on a mission to retain his WBO belt for the fourth straight time since winning the vacant WBO crown in June 2019.

Japan's strict new border controls also forced the postponement of a highly anticipated middleweight unification bout between WBA titleholder Ryota Murata and IBF champion Gennady Golovkin that had been scheduled for Dec. 29. The sides are now aiming to hold that fight in the spring.