European Club Rugby (ERC) are "dismayed and frustrated" at the suggestion by English clubs that the process of reshaping the Heineken Cup is taking too long.
Premiership Rugby chief executive Mark McCafferty insists teams from the RaboDirect Pro12 are given a significant advantage in the Heineken Cup due to the method of qualification.
"ERC should know that we are serious. If it's not resolved, we would go to an Anglo-French competition," McCafferty told the Guardian.
ERC have responded by stating chairman Jean-Pierre Lux and chief executive Derek McGrath have spent the summer seeking proposals from stakeholders that will be tabled at the next meeting in Dublin on September 18. "We are dismayed and frustrated at the position that has been taken by Premier Rugby," ERC spokesman Mark Jones said.
He added: "This is a process that is laid down as part of the accord agreed in 2007. It's not a bolt out of the blue.
"The current qualification process was agreed by ERC's shareholders as part of the 2007 accord.
"This current process is expected and the way it should be.
"We welcome a full review of the tournament and we believe that at the end of the consultation process, European rugby will emerge stronger.
"All of our shareholders have said they want to see European rugby thrive and have agreed this consultation process.
"Our meeting on September 18 in Dublin is the second step in the process."