English-based trio Luke Charteris, Tomas Francis and Josh Adams have been withdrawn from Wales’ summer tour, while Josh Navidi is out injured.
Wales’ opening Test with South Africa in Washington, USA, on 2 June falls outside World Rugby’s official window.
Premiership Rugby Limited, which represents the English top-flight clubs, says the players are therefore not eligible to play in that match.
Rhodri Jones, Ashton Hewitt and Aaron Wainwright have been called up instead.
Although Bath lock Charteris, Exeter prop Francis and Worcester wing Adams are eligible for Wales’ following two Tests in Argentina on 9 and 16 June, Wales need their squad available for the whole tour.
That sees uncapped Dragons duo wing Hewitt and back-row Wainwright along with Ospreys prop Jones added to the squad.
Wainwright gets his opportunity due to the dislocated shoulder suffered by Navidi in Cardiff Blues’ Challenge Cup final win over Gloucester.
The Welsh Rugby Union is understood to be frustrated that PRL has chosen to enforce the rules, despite the three English-based players not being involved in games since the beginning of May.
“The policy of the Premiership Rugby clubs is to comply with World Rugby Regulation 9, and only release players for Test matches inside the official Test window,” said a Premiership Rugby spokesperson.
The three Saturdays within the June international window are 9, 16 and 23 June, with Wales having no extra game in this period.
Wales head coach Warren Gatland said: “We are really disappointed that Josh, Tomas and Luke have to miss out on the opportunity to tour with Wales and play international rugby this summer.
“It was a great opportunity for them to play for their country, press their claim in an important year and it is a shame supporters will not get to see them in the red of Wales.
“The situation is very clear for players playing in England going forward and heading into a Rugby World Cup year.
“With the players unavailable to link up with the squad until the week of our second Test match we have had to replace them in the squad.”
Ospreys-bound wing George North and new Dragons back-row Ross Moriarty are both returning to Wales from Northampton and Gloucester, and so are clear to tour with Wales.
Gatland’s side finish on 16 June with the second Test against the Pumas in Santa Fe, with the Welsh-based players returning a week earlier than England who have a three-Test series in South Africa.
Forwards: Rob Evans (Scarlets) (25 Caps), Wyn Jones (Scarlets) (8 Caps), Nicky Smith (Ospreys) (18 Caps), Elliot Dee (Dragons) (7 Caps), Ryan Elias (Scarlets) (2 Caps), Rhodri Jones (Ospreys) (16 Caps), Samson Lee (Scarlets) (38 Caps), Dillon Lewis (Cardiff Blues) (2 Caps), Adam Beard (Ospreys) (2 Caps), Bradley Davies (Ospreys) (62 Caps), Seb Davies (Cardiff Blues) (4 Caps), Aaron Wainwright (Dragons) (*uncapped), Cory Hill (Dragons) (15 Caps) (Co-Captain), James Davies (Scarlets) (1 Cap), Ellis Jenkins (Cardiff Blues) (6 Caps) (Co-Captain), Ross Moriarty (Gloucester) (20 Caps), Aaron Shingler (Scarlets) (17 Caps).
Backs: Aled Davies (Scarlets) (8 Caps), Gareth Davies (Scarlets) (32 Caps), Tomos Williams (Cardiff Blues) (*uncapped), Gareth Anscombe (Cardiff Blues) (15 Caps), Rhys Patchell (Scarlets) (8 Caps), Hadleigh Parkes (Scarlets) (6 Caps), Owen Watkin (Ospreys) (4 Caps), Scott Williams (Scarlets) (55 Caps), Ashton Hewitt (Dragons) (*uncapped), Hallam Amos (Dragons) (15 Caps), Steff Evans (Scarlets) (9 Caps), George North (Ospreys) (73 Caps), Tom Prydie (Scarlets) (5 Caps).
2018 summer tour schedule
Saturday, 2 June
South Africa v Wales (Robert F. Kennedy Memorial Stadium, Washington, USA)
Saturday, 9 June
Argentina v Wales (San Juan del Bicentenario Stadium, San Juan)
Saturday, 16 June
Argentina v Wales (Estadio Brigadier López, Santa Fe)