Queensland Chief Health Officer Jeannette Young confirmed the trio -  Bryce Cartwright, Nathan Peats and an unnamed third player - would not be able to play after discussions with the NRL about its revised flu-vaccination approach.

As part of biosecurity protocols, the NRL said all players were required to be vaccinated for flu prior to the planned start of the season on May 28.

The NRL also said players could be granted exemptions in exceptional circumstances, including on religious, medical and conscientious grounds.

According to the Sydney Morning Herald, the NRL advised the three Queensland-based clubs of a condition in the exemption granted by the State Government that dictates all 32 players and 18 staff at the teams must be given a flu vaccination.

The "no jab, no play" policy enforced in certain states in Australia has been backed by Australian Prime Minister Scott Morrison.

Young said she was waiting for the NRL to review its vaccination-waiver policy before any changes can be made.

The situation has caused concern in the NRL and threatens the possible start of the season, suspended because of the coronavirus crisis.