World Rugby chief executive Brett Gosper said on Monday it was "unfortunate" the French league (LNR) who run the Top 14 are taking legal action against the sport's global governing body.
The LNR is opposed to the temporary change in extending World Rugby's regulation 9 which forces clubs to release players from domestic matches for Test duty, from three to nine weeks this autumn.
The international window in Europe is set to run from October 24 to December 5 with postponed Six Nations matches being played as well as a new 'Eight Nations' tournament set to include Fiji and reportedly Georgia or South Africa. That will clash with six rounds of the Top 14.
"While it's unfortunate the LNR, the only entity in this process that wants to take a legal approach, feel like that, I think we will get to a constructive place, hopefully and I'm optimistic," Gosper told AFP.
"It's always worrying when someone takes you to court. They have their point of view. The LNR, as the FFR (French Rugby Federation), the PRL (English Premiership) and the EPCR (European Professional Club Rugby) and Pro14 are all working with us.
"Everyone comes with their own agenda, there's a bit of give and take in that room. People realise there is a bigger pie here to talk about for the entire sport and not for their particular corner," he added.
- 'Setting sights on calendar' -
Australian Gosper, who played for French club Racing 92 in the amateur era between 1981-1990, said holding the Tests were financially crucial for naional governing bodies after the impact of the coronavirus pandemic despite some matches being held without fans.
"It's very important for the unions and the federations around the world. That's their inventory for creating money that grows the game and is contributed back into communities and development, high performance and all the rest of it," he said.
"Bringing back games with some broadcasting in particular, some behind closed doors, so not the gate revenues or hospitality you'd want but it's a start and as we gradually ramp up some crowds towards the back end of this year in some countries and into next."
Gosper said discussions regarding permanently changing the sport's calendar to align seasons in the northern and southern hemispheres are ongoing despite concerns from the French and English top-flights leagues.
"What we're setting our sights on is while we've managed the calendar this year in order to give that calendar real estate to those tournaments," he said.
"We're looking beyond that to see what the calendar should be beyond 2020 and organise that in a way that's good for all stakeholders in rugby."