English clubs have revealed their reluctance to release Welsh players for the Probables v Possibles match on March 30.
The match has been scheduled for the day before the Aviva Premiership final and a Premiership spokesman warned that English clubs are likely to refuse to release the players, as they are not obliged to do so by International Rugby Board (IRB) regulation.
The squads for the pre-tour trial match were set to be announced on Tuesday March 13.
But the Premiership spokesman told the BBC: "Premiership Rugby has a policy to only release non-England players under the conditions of the International Rugby Board's regulation nine. This regulation covers international release for every Test country across the world. This trial match does not fall under IRB regulation nine."
Bath duo Paul James and Gavin Henson, Sale's Marc Jones, Saracens prop Rhys Gill, and Gloucester scrum-half Tavis Knoyle may all be prohibited from playing.
Former Wales Captain Ryan Jones, who left the Ospreys for English Championship side Bristol may also be unavailable, as Bristol are party to Premiership Rugby's accords.
France's domestic clubs, are subject to the same IRB regulations so they are also likely to keep hold of their array of Welsh talent. With the Top 14 final taking place on May 31, Wales head coach Warren Gatland will hope that Toulon knock Racing Metro out of the semi final and their Welsh trio, Dan Lydiate, Jamie Roberts and Mike Philips are relieved of their domestic duties.
Write for GiveMeSport! Sign-up to the GMS Writing Academy here: http://gms.to/1a2u3KU