Cardiff have accused West Brom of jeopardising the 'livelihood and career' of Jason Koumas after rejecting their offer for the Wales international.
Albion chairman Jeremy Peace felt the bid, which could have risen to £2million, was well below an acceptable price for Koumas, who spent a successful spell on loan with the Bluebirds last season.
Peace claimed Cardiff had offered £1million plus a further £1million in add-ons, which were 'heavily dependent on the South Wales club winning promotion to the Premiership and staying up for two successive seasons'.
Cardiff confirmed in a statement on www.cardiffcity.co.uk: 'Cardiff City FC has offered WBA £2million divided into three parts.
'One million guaranteed, the other £1million is for games played (which should give them about £0.5million over the player's contract) and the rest if we reach play-offs or get promoted. Effectively, it is highly likely they will get £1.5million and possibly £2million.
'For the purpose of record, WBA have asked for £1.5million guaranteed and £0.5million for add-ons. We tried to give them exactly that on terms we can afford. WBA exercised their right and turned us down.'
But Cardiff believe Albion are 'taking a very hard and unreasonable stance in the transfer saga'.
Koumas has been disciplined by the West Midlands club after failing to return for pre-season training.
A Cardiff statement continued: 'The truth is that they are 100% within their legal right to do what they like. Jason Koumas at this point in time is effectively on strike.
'He is neither meeting his club's hierarchy nor coming to training. WBA are understandably fining him and if he persists they might dismiss him without pay and retain his registration. If that happens, the player will lose both his livelihood and his career.
'As we understand, no club has so far made an offer that is acceptable to WBA - this is given the fact that he has not been with them for over a year.
'So WBA have no real offer from anyone. They turn down a lot of money to sell for what they asked for but on different payment terms. They turn down a lot of money to loan. A player's livelihood and career may be ruined. Where is the logic in that?'
West Brom, who described the cardiff statement as 'bizarre', have responded to the comments by insisting Koumas will remain at The Hawthorns unless their Championship rivals meet their required terms and will not be rejoining them on loan.
A statement on: 'We quite properly expect Jason to meet the obligations of his contract, for which he is handsomely paid.
'We therefore take great exception to Cardiff's suggestion that we are not acting in a 'humane' manner, particularly given that the club have gone out of their way in attempts to reintegrate Jason back into the squad.
'Cardiff have commented on several sensitive issues regarding Jason's situation which, while he remains an Albion player, are, quite frankly, none of their business. We now consider this matter closed.'