World Rugby's move to smooth out the international calendar seems to have hit a roadblock before it's even begun.
This week, several unions and the international players' body will meet in Dublin to deliberate over the controversial new global rugby competition.
But France's Ligue National de Rugby and England's Premiership Rugby have voiced their anger at being left out of the gathering of high-powered rugby officials.
On Tuesday (NZ time), they issued a joint statement to express their concerns, hinting at legal action, if World Rugby proceeds with its proposed plans to restructure the international game.
The two competitions claimed that the proposed multi-tiered Nations Championship goes against an agreement among stakeholders two years ago to cement the global rugby schedule through until 2032, by including more tests in November and December.
"It appears the new competition plan now challenges this balance by increasing the number of international matches," they said in a statement.
"The professional leagues now seem to be excluded from this new work, even though the World Rugby project would be a major change to the San Francisco agreement for all elements of the professional game and impact other competitions."
Both also stated that the perceived lack of consensus by World Rugby making the decision means they "reserve the option to take any action to preserve their rights and competitions".
That could also include withholding players from international duties. The clubs are currently only obliged to release them for three games in June, three in November and for the Six Nations tournament.
World Rugby's meeting begins on Thursday.