Tournament chief executive Jon Dutton admitted at a news conference that Australia have yet to sign the participation agreement and Troy Grant, chairman of the International Rugby League, revealed officials have identified potential replacements in the event of any teams withdrawing.
But Dutton says organisers have put a team in place in Sydney in an effort to get a deal over the line and he is confident of being able to avoid a similar situation to 1995, when Australia came over for the World Cup with an under-strength team at the height of the Super League war.
Dutton said: “We do expect all 21 nations to come to the UK. We met with all of them earlier in the week.
“We appreciate there are still some challenges for us to work through.
“But we wouldn’t be making this announcement today if we didn’t have the confidence that those nations would arrive in this country and compete in the tournament.
“It’s really important for us to take away the uncertainty and to build confidence.”
The tournament will kick off on October 23 when England face Samoa at Newcastle’s St James’ Park, the first of 61 matches across the men’s, women’s and wheelchair competitions which will all be shown live by the BBC.
The men’s and women’s finals will be played at Old Trafford on November 27 and Dutton says ticket sales have far exceeded expectations.
Grant said: “The World Cup going ahead this year is critical. There was no international rugby league in 2020 and it was sorely missed.
“If it didn’t happen there could be immense damage to the reputation of the international game.”
Half of the 16 men’s teams will come from the southern hemisphere and Dutton confirmed his organisation will foot the bill for charter flights to bring the 400-plus players and officials from Australia as well as ensuring other bio-security measures are put in place.
Dutton, who was involved in the successful staging of the 2013 World Cup in the UK and began preparations for the 2021 tournament more than five years ago, had delayed a final decision over the last three months and admitted he had passed the point of no return.
“Today marks 100 days to go and we believe this is the right moment to take away any remaining uncertainty,” said Dutton, who confirmed he had considered both a postponement and a cancellation.
“We have got great momentum and there is a resounding desire from UK Government as part of the reopening and rebuilding of confidence here in the UK for the tournament to go ahead.
“We have seen how incredible the football European Championships were and we’re now seeing international athletes travel all over the world in a safe environment to play their sports.
“This tournament is bigger than sport and bigger than rugby league, this is our moment to shine.”
Dutton says vaccination for players will not be made mandatory but there are plans for a testing regime and a hybrid bio-secure bubble and he says some of the restrictions set to be lifted next Monday – like social distancing and face masks – will be retained.
He added: “We need to create a balance between a life experience and player safety.
“Safety is of paramount importance but I would describe the bio-security measures that we have already put in place and incredibly similar to what is being experienced with the Indian cricket team.
“I think the additional measures we need to put in place are small and I am very confident we can do that over the next few weeks.”