The International Rugby Board say they will review the eligibility of Steven Shingler after a row between Scotland and Wales over the Swansea-born player's decision to play for Scotland.
Shingler, 20, was named in Scotland's Six Nations squad on Thursday despite having played Welsh international junior rugby.
Scotland coach Andy Robinson picked the London Irish first five/centre on the grounds that he has a mother born in Scotland.
However Wales Rugby Union officials later pointed out that Shingler had already played for Wales Under-20s last year and was therefore tied to Welsh rugby at international level.
With the two unions unable to find agreement, the IRB has confirmed it will review the case.