New Zealand have been given a Monday deadline to agree to plans for next year's World Cup or face being removed as co-hosts.
New Zealand rugby chiefs have so far refused to compromise on the date of their premier club competition, the National Provincial Championship (NPC), even though it clashes with the World Cup in October and November.
The International Rugby Board has called for the tournament to be moved and, as a result, New Zealand have yet to sign official papers installing them as co-hosts.
The World Cup is to be officially launched on March 12th and an IRB spokeswomen told the London Times: "They have five days to agree and sign up.
"One option would be to remove them from hosting the tournament leaving Australia to host the World Cup on its own. That would be a decision for the directors of RWC (Rugby World Cup Limited)".
However New Zealand Rugby Football Union chief executive David Rutherford said: "I am confident of resolution on the NPC matters provided a reasonable approach is taken all-round".
PA