Terry Flanagan has accused fellow Mancunian and lightweight world champion Anthony Crolla of ducking him.
Flanagan, 27, defends his WBO title against South Africa's Mzonke Fana at the Manchester Arena on 9 July.
Crolla, 29, defends his WBA title against Venezuela's Jorge Linares at the same venue on 24 September.
"We offered Crolla the fight and he didn't want it. If he wants the fight, he should go to his coach and promoter and say he wants it," said Flanagan.
"It's probably the people around him who are worried about the fight, but it's Crolla's decision at the end of the day.
"It's an easy fight to make. Frank [Warren, Flanagan's promoter] isn't making it hard for them. If anything, he's bending over backwards to make it happen.
"He's giving in to their demands. He's said they can have it on Sky Sports [with whom Crolla's promoter Eddie Hearn has an exclusive deal], but still they don't want it.
"If we both keep winning, it might happen down the line, but I'm not confident it will. He knows my style will give him problems and I don't think his team believe he can beat me.
"It's a shame because Anthony's a great fighter and he has looked really good in his last three fights. Let's just make proper fights and have the best fight the best. Don't be scared to lose."
Flanagan, who is unbeaten in 30 professional fights, is making the third defence of his title against the 42-year-old Fana, a former super-featherweight world champion who made his pro debut in 1994.
"People say: 'Why are you fighting this old man [Fana]?'" said Flanagan, whose most recent defence was a points victory over Liverpool's Derry Mathews in March.
"We want the big fights that the fans want to see. All we can do is keep pushing for them and hopefully one of them will come off."
Warren says he made Crolla an offer of £500,000 to fight Flanagan and that Crolla chose to fight mandatory challenger Ismael Barroso instead.
In the first defence of his title last month, Crolla stopped the previously unbeaten Venezuelan, improving his record to 31 wins from 38 pro fights.
Both Barroso and former WBC champion Linares stopped Britain's Kevin Mitchell last year.