The fight in Riyadh, originally proposed for December 23rd and then set for February 17th, has been rescheduled for the Saudi Arabian city on May 18th.
The 'Ring of Fire' clash will unify Fury's WBC heavyweight championship with Ukrainian Usyk's WBA, IBF, WBO and IBO belts, crowning the first unified heavyweight boxing champion since 1999.
Usyk told reporters in a press conference at his training camp on Spain's eastern coast that he had sacrificed a lot to prepare for the fight and Fury should take the fight more seriously.
"I sacrificed all the days that we used to spend with my family; New Year, Christmas, my birthday, the birthday of my son, the birthday of my second son, and of course the birth of my daughter," he said.
Usyk said he would now spend two or three days at home, to hug his daughter and be with his wife, before returning to training.
He said he had been sparring in the ring when he was told about the latest postponement, and questioned Fury's training methods.
"I'm not judging anyone, but the thing is that we have to treat this more seriously. This is a very important and well anticipated fight for the whole world," he said.
"There are certain measures taken by highly professional fighters, normally you use the head gear, using the big gloves, like 20 ounce gloves, for sparring.
You apply Vaseline on the gloves of the sparring partners, you apply Vaseline on your mask, on your eyebrows, to avoid cuts, to avoid any kind of injuries.
"Because you are treating this in a different manner than a professional you are jeopardising the whole event and you behave disrespectfully to people who are involved."
Fury said earlier in the week that he had never before suffered a cut in sparring for a big fight.
