Press Association Sport understands the IRB is ready to call all six top unions and relevant club bodies to a summit meeting to broker a final solution to the European wrangles.
No meetings are yet scheduled, but the IRB issued a statement on Wednesday night, formally entering the European dispute for the first time.
Concerned at the lack of a "common solution", the IRB pledged to fight for the "establishment of a truly representative pan-European rugby competition that fully complies with IRB regulations".
The IRB now hopes to end the impasse that was sparked by the English and French clubs giving notice in June 2012 they would not sign a new agreement with Heineken Cup organisers European Rugby Cup (ERC), when the tournament contract expired in summer 2014.
IRB chairman Bernard Lapasset said: "In order to reach an outcome that is in the best interests of rugby globally, the IRB will work actively with its unions towards the goal of achieving a unified and acceptable outcome for all stakeholders involved."
The RFU and Premiership Rugby (PRL) both threw their weight behind the IRB intervention, building fresh hope for a resolution.
The IRB did reiterate the world game's governing body cannot support any cross-border competition unsanctioned by relevant domestic unions.
That would severely damage the likelihood of a new Anglo-Welsh league, one of the counter proposals from Premiership Rugby if there is no full European contest next season.
But PRL reasserted their own commitment to a full Europe-wide resolution.
A Premiership Rugby spokesman said: "Over the last 18 months we have repeatedly made several different proposals for a pan-European rugby competition.
"These have even included a third-tier competition for developing nations, all of which benefit the whole of European club rugby.
"The clubs clearly understand any cross-border competition must be put before the unions of the regions, provinces and clubs participating."
It is understood the IRB expected the good feeling fostered by productive meetings at Heathrow on October 22 to lead to a quick resolution of this long-running dispute.
The hiatus since has led the world game's governing body to add their voice to the issue in an extra bid for mediation.
The English and French clubs want a fairer distribution of tournament revenue, and are pushing their TV rights deal with BT Sport, while ERC believes Sky hold broadcasting control beyond 2014.
It is understood revenue wrangles can be resolved by a three-way split between English, French and Celtic clubs.
Tournament governance remains the big sticking point however, with PRL and the French clubs now keen to see the RBS 6 Nations organisers assume control of the top European competition.
ERC naturally oppose that shift, and it is thought the Irish provinces are still similarly aligned.
The RFU are clear on prioritising a swift solution to include all six frontline European countries in a revamped competition.
RFU chairman Bill Beaumont said: "Our primary focus should be to maintain a genuinely pan-European tournament.
"Rest assured I am working closely with RFU CEO Ian Ritchie and other stakeholders to find a solution.
"I welcome the support of the IRB in helping to ensure that this happens and of course as a member union abide by and support the IRB regulations."
- Sports & Recreation