The Australian Rugby League Commission and NZRL released a joint statement on Thursday afternoon citing player welfare and safety concerns as reasons for the withdrawal, urging the UK tournament be postponed until 2022 due to the COVID pandemic.

Organisers are fuming, claiming they were given just four minutes' notice before the statement was released.

IRL chair Troy Grant says players are also unhappy they have not been allowed to make their own call on whether they want to play in the tournament.

"I have been in regular communication with the RLPA and a number of international players and coaches who have been satisfied with the World Cup's biosecurity arrangements and expressed a clear determination to travel to England and proudly represent their nations," Grant said in a statement.

"They have expressed to me that they feel their own personal choice to participate or not in the World Cup has been taken from them.

"The RLPA have again committed to continue to work with IRL and the Local Organising Committee towards a 2021 tournament including Australian and New Zealand players who have dual eligibility and who are now keen to play for other nations."

The withdrawal of the Kangaroos and Kiwis has left organisers scrambling to reconfigure the tournament, with Grant admitting it's unclear if it will even go ahead.

"We will be reconvening to consider our options and next steps once the RLWC2021 Board and UK government have had time to consider and absorb the news themselves," he said.

"My job from here is to understand the LOC's and UK government's attitude towards continuing with the RLWC without Australia and New Zealand, if that is a viable option, or consider other options available to us.

"The next week will be critical but despite whatever happens my job as IRL chair is to pick up the pieces of international rugby league's tarnished reputation as a result of these decisions."

But the ARLC and NZRL said that the current environment in the UK was just too risky for athletes and officials.

Extended time away from home including quarantine periods after the November 27 final was also cited as a reason for withdrawal.

ARLC chairman Peter V'landys said the call was made to protect the wellbeing and safety of players and officials.

"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," he said.

"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."

Earlier this week the UK lifted the majority of COVID-19 restrictions while case numbers continue to climb both there and in Australia.

"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," said NZRL chief executive Greg Peters.

"We understand how disappointing this is for fans and those involved, however, player and staff safety remains paramount."

Australian Associated Press