A ground-breaking first Rugby World Cup in the Americas is now unlikely to take place until 2031, with Australia emerging as a prime contender to host in 2027.
France will stage the tournament in four years' time.
A southern hemisphere country is then expected to host, with a breakthrough event in the USA now lined up for the following tournament.
The formal bidding process for 2027 and 2031 starts next November.
'Australia an important rugby nation'
Australia have already announced their bid to stage the event in eight years' time, with administrators down under seeing it as an opportunity to revive a flagging rugby nation, especially given their strong track record of hosting major tournaments.
And despite their recent difficulties on and off the field, Australia remains a crucial part of the global landscape, says Bill Sweeney, chief executive of England's Rugby Football Union.
"You would think 2027 would need to go somewhere southern hemisphere," Sweeney told the BBC.
"Australia is a really important rugby nation, who have had some financial challenges.
"Anything that World Rugby can do to support the game in Australia would be supported by all of us, I think."
A southern hemisphere World Cup also brings South Africa strongly into the equation after they narrowly missed out to France to host in 2023.
The South African Rugby Union - buoyed by the Springboks' status as world champions - is considering another bid, but has yet to confirm.
USA in 2031?
Meanwhile World Rugby is desperate for the sport to catch fire in the USA, and a bid for the 2031 showpiece would allow more time for rugby union to develop in the States, with Sweeney adding that there was "a massive opportunity for the game to kick off" there.
Hosting in 2031 rather than 2027 would also avoid the rugby showpiece being sandwiched between the Football World Cup in 2026 - which is hosted by the USA, Canada and Mexico - and the Los Angeles Olympics in 2028.
The governing body is also open to a joint bid from the USA and Canada, while a South American Rugby World Cup - revolving around Argentina and Uruguay - is another intriguing option.
Russia, another emerging rugby nation, have also confirmed an interest in staging the tournament for the first time.
With the bidding process starting in November 2020, the host nations for 2027 and 2031 World Cups will be announced together at some point in 2021.