World champions South Africa are being lined up to replace Japan in an eight-team tournament at the end of the year.
The Brave Blossoms, who hosted last year’s World Cup, pulled out because of coronavirus travel restrictions.
Georgia were touted as replacements but World Rugby vice-chairman Bernard Laporte says they are now in “advanced discussions” with South Africa.
“It would be great to be able to face the Springboks, world champions, but it’s not yet done,” he said.
A spokesperson for South Africa Rugby said they had “no knowledge of such an arrangement being planned”.
The tournament is replacing the autumn Tests and will begin on 14 November – two weeks after the final round of the 2020 Six Nations is completed.
South Africa could join group two, which is currently occupied by Scotland, Italy and France, and needs a fourth nation.
Group one comprises England, Wales, Ireland and Fiji, with the two pool winners scheduled to meet in a final at Twickenham on 5 December.
Meanwhile, BBC Sport understands England’s players have agreed to take a 25% cut to their match fees during this autumn’s fixtures, a reduction of about £6,000 per match.