The Kangaroos will not travel to England to defend their title at the 2021 Rugby League World Cup.
The Australian Rugby League Commission and the New Zealand Rugby League released a joint statement on Thursday afternoon informing tournament officials neither team will compete in the event due to "player welfare and safety concerns."
Both national bodies requested the World Cup, which is scheduled to kick off on October 23, be postponed until 2022 to minimise the risk of players catching COVID-19.
It comes just a week after World Cup organisers confirmed it would be going ahead as planned this year, confident they could assure the ARLC to sign the participation agreement by enforcing strict bubble conditions for participating athletes.
But not even that could persuade the ARLC and NZRL that the risk is worthwhile, saying in the current environment in the UK the risk is too great for athletes and officials.
Extended time away from home including quarantine periods was also cited as a reason for withdrawal.
The timing of the tournament was also a concern for NRL clubs with players to then quarantine for two weeks upon arrival back in Australia after the November 27 final.
Players would then be entitled to annual leave under their NRL contracts which would mean they wouldn't return to preseason training until late January.
"Not participating in this year's World Cup is not a decision the Commission has taken lightly, but we must put the best interests of our players and officials first. Protecting them is our absolute priority,'' ARLC chairman Peter V'landys said.
"In the current environment, the risks to the safety, health and wellbeing of the players and officials travelling from Australia to participate in the tournament this year are insurmountable.
"The majority of NRL players are currently living away from home under difficult biosecurity protocols. They would then be required to remain under protocols and away from home for the duration of the tournament before again quarantining on return to Australia. This is too much to ask our players and officials to do.
"We have again requested the IRL and Rugby League World Cup consider postponing the event until 2022 to enable all players to participate."
NZRL boss Greg Peters also noted the difference in how the COVID-19 pandemic is being managed between the UK, Australia and New Zealand.
The host nation is still reporting thousands of cases per day, while the recent outbreaks in Australia are also a cause for concern.
"The safety and wellbeing of our people is the main priority, and unfortunately, that cannot be guaranteed to our satisfaction," he said.
"There are stark differences between how the pandemic is being managed in the UK compared to Australasia and recent developments have highlighted how quickly things can change.
"The tournament organisers have moved heaven and earth to make this work, so it is not an easy decision, but the Covid-19 situation in the UK shows no sign of improving, and it's simply too unsafe to send teams and staff over.
"We understand how disappointing this is for fans and those involved; however player and staff safety remains paramount."
Australia has claimed 11 World Cup titles, including the last two, while New Zealand won the tournament in 2008.