Regional Rugby Wales - who represent the four Welsh regions - have called for an independent enquiry into revenue distribution.
In a statement issued on Sunday the umbrella company for the Blues, Ospreys, Scarlets and Dragons called into question the revenue received from broadcasting and competitions.
The statement highlighted the differentials between their own regions and the funds received by other nations as the bad blood with the Welsh Rugby Union continues.
All four regions previously declared to leave the Heineken Cup next season, with the WRU declaring it would be part of reformatted competition.
"Regional Rugby Wales, on behalf of the four Welsh Regions, have today confirmed that they are requesting an Independent Public Enquiry into the current and projected distribution of Broadcasting and Competition revenues into the Professional game in Wales," read the statement.
"Specifically, the Regions' request an Independent Review to properly consider the following questions:
"Why is it appropriate for the Scottish Clubs operating in the Union's ERC competition to receive an approximate distribution of €2.45m per team when the Welsh Regions receive only €1.225m per team?
"Why is it appropriate for the Italian teams operating in the same competition to receive approximately €2.3m per team?
"This is the existing position and we have received no assurance that it would not continue under the new 5 Nation European Competition proposed by the Unions.
"With the French clubs being able to negotiate TV revenues well in excess of €65m for their Domestic League, why is the revenue from French TV for the proposed new 5 Nation European Competition, negotiated by the Unions estimated to be only €14m?
"With the English clubs being able to negotiate TV revenues of £22m from their domestic league, why are the Unions only able to achieve revenue of £5.5m for primary TV rights for the RaboDirect Pro12 league?
"With the significant proposed contribution of £3.2m from Welsh television to secondary TV rights for Pro12, why is the estimated contribution from Irish TV only £910,000 and from Scottish TV only £140,000?
"Based on all of the above, have imbalances or subsidies built up in TV revenues between the various International and Club competitions negotiated by the Unions and if so, how did this arise?
"If this is the case, how can it be corrected going forward to ensure the Regions have the resources to retain and grow the pool of Welsh Professional players to adequately service the Professional game and the Welsh National team?"