World champion Carl Frampton has criticised Scott Quigg's promoters for a televised offer to fight.
WBA super bantamweight champion Quigg and promoter Eddie Hearn appeared on Sky with a £1.5m cheque, which they promised Frampton if he took the bout.
But representatives of the Belfast fighter say there have already been "several attempts" to meet Hearn.
"It is frustrating they have deviated from negotiations with this TV offer," said Frampton, 28.
Frampton's camp say the eagerly-awaited fight can only happen as a co-promotion between Barry McGuigan's Cyclone Promotions and Hearn's Matchroom Sport.
But Hearn told BBC Sport: "It's not about either promoter, it is about Carl Frampton and Scott Quigg.
"We were getting nowhere with discussions so we are trying to make things happen - £1.5m is considerably more than Carl Frampton can get anywhere else in the world for any other fight.
"He will know it is an incredible amount of money and an offer too good to refuse."
The camps met to discuss the fight for the first time formally on 25 March.
Unbeaten Quigg, 26, successfully defended his super-bantamweight title for a fifth time in November with a unanimous points win over Hidenori Otake, while Frampton stopped Californian Chris Avalos to retain his IBF belt in March.