“The WRU has failed miserably to negotiate equitable and fair revenue distribution for Welsh clubs”
Regional Rugby Wales statement
The letter to the clubs stated that the regions intend to break away from the WRU after 30 June, 2014 when the existing agreement expires if no new deal is reached.
It was signed by the WRU's group chief executive Roger Lewis, chairman David Pickering and president Dennis Gethin.
But RRW claims the WRU is "scaremongering" about a split, saying: "This has never been mentioned by the regions, who have only asked for positive support as outlined in their most recent
statement of 31st December.
"As stated then, it continues to be the absolute intent and strong desire of RRW and the regions to work with the WRU... for the next five years of professional rugby in Wales, or indeed to discuss any proposals the WRU [has] ...for sustainable and competitive professional rugby across Wales."
The WRU says that because of contractual obligations it could not sanction an Anglo-Welsh league, which the regions believe is a strong option to safeguard their financial future as businesses.
has been reported
that Premier Rugby Limited, which represents the top-flight English clubs, and its broadcast partner BT Sport have offered each region £4m a season to quit the Pro12 and instead compete in an Anglo-Welsh competition.
There is also uncertainty surrounding
the future of the Heineken Cup,
with the English Premiership Rugby clubs and the French Top 14 sides previously threatening to withdraw from it in favour of a new cross-border competition.
A new European competition has been proposed under the name of the Rugby Champions Cup, to replace the Heineken Cup and second-tier Amlin Challenge Cup once the current European Rugby Club accord runs out at the end of the 2013-14 season.
The strongest response from RRW is over the WRU's stance that it will also not sanction a new European tournament to replace the existing competitions, unless it has "been agreed by the International Rugby Board".
"The Rugby Champions Cup will bring the biggest increase of funding into the Welsh game in five years," read the RRW statement.
"It will increase funding to the Irish clubs and protect the Scottish clubs. Bringing in £12m in three years into the Welsh game does not threaten the Six Nations or bring about its demise."
The Scrum V debate: The future of Wales' rugby regions
The statement continued: "The WRU not only has full responsibility, but is also contractually obliged to negotiate competition revenues and TV distribution revenues under the participation agreement.
"The WRU has failed miserably to negotiate equitable and fair revenue distribution for Welsh clubs in line with clubs in England and France."
RRW claims that a new ERC accord would be for "an inferior competition" and that the WRU letter constitutes an attack on the four regions.
"It's disappointing that the WRU's disrespectful response to another significant and positive proposal... is once again to engage in a vitriolic and disingenuous attack on the Welsh regions, with the purpose of detracting attention away from the real issues Welsh regional rugby is facing," claimed RRW.
The WRU is legally obliged to enter four teams in the Pro12 and Heineken Cup next season. If there is a split with its regions then one option for the WRU would be to create four new sides to represent Wales.
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