Promoter Frank Warren and David Haye's camp each insist that the other side is to blame for the cancellation of April's fight with Enzo Maccarinelli.
Maccarinelli (left) and Haye will be a huge crowd-puller
Adam Booth, Haye's trainer and manager, said his man still wants the bout to take place as part of a "one-fight deal" he claims Warren had agreed to.
But Warren responded, insisting Team Haye had accepted a counter offer which "made the original offer invalid".
Haye and Maccarinelli were set to fight for the WBO cruiserweight title.
Warren wanted the much-anticipated meeting to go ahead on the undercard of Joe Calzaghe's WBO super-middleweight title defence against Peter Manfredo in Cardiff's Millennium Stadium on 7 April.
Speaking on Sunday, Booth said: "If Frank still wants to do it as the one-fight deal with no strings attached, then it is on.
"We have in writing a faxed offer for a one-fight deal which we accepted.
"However, Frank later withdrew that offer and proposed a number of options which were totally unacceptable.
"We have agreed the money and everything else, and we made no last-minute changes to our demands."
However, Warren claimed on Monday that the Haye camp had agreed a number of options for their man beyond the original fight.
"Matters had gone way beyond the 'one-fight deal offer' recently raised by Booth," said a statement.
Maccarinelli is still expected to defend his WBO title on the Calzaghe bill before hopefully facing the winner of the fight between O'Neil Bell, the WBA and WBC champion, and Jean-Marc Mormeck.
The 26-year-old Welshman inherited the title when champion Johnny Nelson was forced to retire ahead of their title bout because of injury problems.
A former WBU champion with 25 wins from 26 fights, he defended his WBO title against Mark Hobson, knocking out his opponent in the first round of their fight in October.
Haye, the European cruiserweight champion, stopped Italian Giacobbe Fragomeni in the ninth round of his last fight. The Londoner, also 26, has 18 victories from 19 outings.