The Sunwolves will not take part in Rugby Australia's proposed Super Rugby AU competition it was announced on Monday morning.
RA and Japan-based Sunwolves had worked together for several weeks to provide the side the opportunity to participate in the Australian-based competition, but despite their efforts both organisations came to the conclusion that it would not be possible.
In a statement on Monday, RA said COVID-19 prevented the team from having adequate time to prepare for a planned July 3 kick-off.
Current Australian border restrictions would require the Sunwolves to complete a 14-day quarantine period within a hotel before they could return to training. The team would also need to establish a permanent base in Australia for the 12-week competition.
"There are significant challenges facing the Sunwolves' participation in this modified competition model which Rugby Australia, SANZAAR and the Sunwolves have been attempting to work through," Rugby Australia interim CEO, Rob Clarke said.
"However, the reality is, given the timeframe available the team's preparation for the competition would be severely compromised.
"All parties agree that despite our collective efforts and desire to see the Sunwolves take part in the competition, under the current circumstances their participation will not be feasible. While unfortunate, this decision delivers the certainty that all stakeholders require at this point in time.
"We all agree that this is not the way we wanted or believed that the 2020 Super Rugby season would play out when it kicked off back in late January, the impact of COVID-19 has been unprecedented and unforeseen."
The 2020 season was the last for the Sunwolves in the Super Rugby competition with it was announced in March 2019 after the Japanese Rugby Football Union failed to negotiate a contract for financial reasons.
Joining the competition in 2016, the Sunwolves recorded just eight wins in their four seasons, however garnered a fan base around the world.
Super Rugby AU is penned to kick off July 3 with all four Australian Super Rugby sides and the Western Force to play out a 12-week competition, dependent on broadcasters sign-off.
New Zealand's Super Rugby Aotearoa kicks off June 13 with all five Super Rugby sides to play a home and away season across 10 weeks.