Sky Sports understands Nottingham Forest have failed to win work permits for three of their Kuwaiti trialists.
Following the club's takeover by Kuwaiti family the Al Hasawis a number of players from the Middle East were offered trials at the City Ground.
Striker Bader Al-Mutawwa, central defender Hussein Fadel, and goalkeeper Khalid Al-Rashidi have all been on trial at Forest so that Sean O'Driscoll could cast an eye over them in training.
The trio are thought to have impressed O'Driscoll and his coaching staff with the club moving to try and sign them.
However, the moves have been blocked after the Home Office refused to sanction work permits for the Kuwaiti trio.
The news is a blow for O'Driscoll as he looks to bolster his squad before the close of the transfer window next week.
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