Leeds prop Kylie Leuluai will not be joining Hunslet on a dual-registration deal after the UK Border Agency blocked the move.
The Hawks had announced earlier this week that Leuluai, and fellow Rhinos prop Richard Moore, would line-up for them this weekend against Leigh.
However, under the terms of his visa, Leuluai is unable to play for the Championship side.
An RFL statement said: “The RFL has recently lobbied the UKBA for a change to the rules which prevent players on Tier 2 visas playing for a second club on a short-term arrangement. This follows on from changes to the Super League Academy structure, which from 2013 is an exclusively under-19s competition, an arrangement that means open-age overseas Tier 2 visa players returning from injury cannot gain match fitness on short-term loans or dual registrations.
“Dialogue with the UKBA continues but the UKBA have confirmed that until any change in circumstance is agreed, under existing provisions no player on a Tier 2 visa can be dual registered.”
The RFL’s Operational Rules state that they will not at any time accept a registration application for an overseas players, nor register the player, until it has received a copy of the player’s visa showing that the player is entitled to work in the country.