Pro12 holds talks over expanding into north America
Pro12 officials have held talks that could lead to north American teams joining the competition in the future.
Four teams each from Ireland and Wales plus two each from Scotland and Italy make up the current format.
The possibility of the Six Nations moving to a spring start has encouraged hopes of Pro12 expansion.
"We've had really early discussions, with USA Rugby, broadcasters, sponsors," said Pro12 managing director Martin Anayi.
He wants the annual tournament involving England, Ireland, Scotland, France, Wales and Italy moved in the calendar and expects international governing body World Rugby to help that happen.
Speaking at the launch of the 2016-17 Pro12 season in Dublin, Anayi underlined the desire for north American teams to be included, with Houston and Vancouver having been earmarked as possible host cities.
|More from BBC Wales Sport|
|Dublin to host 2016-17 Pro12 final|
|The men behind Swansea City's money|
|Swans keeper signs new deal|
He said: "Everyone's saying the same things, that if it's good for the tournament across a whole range of areas, player welfare, if it's good commercially, for the fans, and does it form part of their strategic plan too, then we should explore how far we can take it.
"They believe in the same things we do, which is the only way for a tier-two nation to become a tier-one nation is through professional club rugby.
"Because there is no scope to expand the international calendar, for the USA to play more games."
However, Anayi accepts that a long-talked-about global season has to be implemented for any Pro12 revamp to take place.
"You've got to talk about why it is that we're losing a huge proportion of international players not week in and week out, but in big chunks of the season," said Anayi.
"Intersperse that with European club rugby as well and you get quite a disjointed season.
"We think there's a simple solution, which is to push the Six Nations back and finish the club season before the Six Nations.
"We'll be really, really sure about our future and how successful club rugby can be globally if we can just get to the point where we get our international players playing in a consistent fashion."