The signing up of a New Zealand rugby union coach by Wales has prompted the New Zealand Rugby Union to seek legal advice.
It has accused the Welsh Rugby Union of sidestepping International Rugby Board rules.
Wales had hired without consultation one of New Zealand's contracted personnel, Crusaders Super 12 assistant coach and Canterbury provincial coach Steve Hansen.
Hansen is to be assistant coach to Wales coach Graham Henry, also a New Zealander, from November.
The lack of consultation was in breach of IRB regulations, NZRFU chief executive David Rutherford said in a statement.
"No union can induce or attempt to induce any contracted player or coach to leave their union unless the prior written consent of that union has been obtained," he said.
"I made it clear that we were seeking legal advice in Britain and we would be guided by that advice," Rutherford said.
The NZRFU said it was important to protect the sanctity of contracts between players, coaches and national rugby unions.