MotoGp organisers say Phillip Island risks losing the Australian Motorcycle Grand Prix after next year unless it switches to a March date.
Dorna, which promotes the series, says that unless the change is made, the race will not be approved and will not go ahead.
But the Australian Grand Prix is adamant it will remain in its October timeslot until at least the end of the contract extension, which runs until 2016.
The timing of the race has been criticised by several riders, led by seven times world champion Valentino Rossi, who says cold weather and fierce winds ruin what should be a showcase event.
Dorna boss Carmelo Ezpeleta says the 2011 GP will go ahead from October 14-16, but from then on the race must be brought forward.
