The Rugby World Cup could increase to 24 teams by 2023 as the governing body considers expanding from 20 countries.
Japan will host the 2019 World Cup, with next year's tournament to feature 20 teams – New Zealand looking to claim a third successive title.
Canada, Kenya, Hong Kong and Germany will contest a round-robin play-off event in Marseille to decide who qualifies for the 2019 showpiece.
However, France 2023 could include four more nations, according to World Rugby CEO Brett Gosper.
"We're always looking from an expansive point of view rather than reducing so it's just a question of when rather than if," Gosper said.
"We want to make sure the teams are competitive enough to move to a 24-team tournament. We have assumed 20 for 2023 but we could change that between now and 2023.
"The tendency for us is to try and look to expand. It's about growing the global game - getting interest from fans and commercial interest in new markets.
"But you've got to make sure you've got the teams. We're definitely in an expansive mindset, is how I'd put it."
Amid concerns of a mismatch against the likes of the All Blacks at the World Cup, Gosper added: "We'll work hard after that team qualifies to ensure they've got all the technical coaches they need - as we do for each World Cup.
"We are confident that team that qualifies will be competitive enough, even against the All Blacks."
