A meeting between the champion clubs of European and southern hemisphere rugby seems to be edging closer, although "planning is at an early stage".
European Professional Club Rugby (EPCR) says it is talking to southern hemisphere governing body Sanzar about organising a game "in the future".
Toulon won the European Champions Cup in 2015 while New Zealand's Highlanders are the reigning Super Rugby champions.
EPCR said it was working on "how best to organise and market" a match.
A statement from EPCR said it had to "ensure that any such match would be incorporated into the global season at the appropriate time".
The final of European Champions Cup is usually in May, while Super Rugby is played from February to August.
Super Rugby expanded to 18 teams for the 2016 competition, with three franchises being added - South Africa's Southern Kings, Argentina's Jaguares and Sunwolves of Japan.