WBA and WBC world middleweight champion Gennady Golovkin has been stripped of his IBF title for failing to agree to face a mandatory challenger.
The Kazakh fighter, 36, was asked to fight Sergiy Derevyanchenko by 3 August but a deal has not been done.
Golovkin won the title by beating Canadian David Lemieux in 2015 but it is now vacant. Britain’s Billy Joe Saunders holds the WBO title.
The IBF will identify “two leading contenders” to fight for its belt.
In a lengthy statement, the IBF said Golovkin had asked in April not to fight Derevyanchenko as he had already agreed a bout with Vanes Martirosyan for 5 May.
He was fighting Martirosyan as a result of a rematch with Saul ‘Canelo’ Alvarez being postponed when the Mexican failed a drugs test.
The IBF agreed to Golovkin’s request on the proviso he would agree to a bout with Derevyanchenko by 3 August.
There have been reports Golovkin and Saunders are close to reaching an agreement to fight.
Saunders, 28, has twice pulled out of a title defence against Martin Murray because of injury.