Leeds Rhinos insist they have first refusal on Iestyn Harris following his decision to return to rugby league. Harris has been linked with a move to Bradford Bulls but Leeds believe there is a clause in his contract which means he must come back to Headingley.
"The situation is confusing," said Rhinos chief Gary Hetherington.
"We would be disappointed if any other rugby league club were attempting to frustrate this contract or Iestyn was seeking to renege on the agreement".
Hetherington added: "We are waiting to hear from Iestyn."
Harris joined the rugby union ranks three years ago and has 12 months left to run on his current deal with the Welsh Rugby Union (WRU).
But the 28-year-old has decided to bring an early end to his spell in the 15-man code.
Bradford say they have not held talks with the Wales centre concerning a return to rugby league, a spokesman calling transfer stories "pure speculation".
But the Cardiff Blues admit they are resigned to losing Harris, although they do not know his intended destination.
Robert Norster, the Blues' chief executive, confirmed they had received notification of Harris' intentions to return to rugby league.
"The complex contractual arrangements provide Iestyn with an option to terminate his commitments with Cardiff Blues", said Norster.
"Like the WRU, we are disappointed with the level of direct communication with the player.
"But our coach David Young did receive a brief telephone call from Iestyn immediately prior to his holiday to inform him of his family decision to return to the north of England.
"Like the WRU and Leeds Rhinos, who hold an option on the player, we are not presently aware of Iestyn's intended destination.
"Consequently, we await further developments and are in discussions with all affected parties, including the WRU's lawyers".