Northampton have accepted they are "outside Premiership Rugby board policy" after their Wales wing George North was released for Saturday's Test match against Australia in Cardiff.

But the club also say their agreement with North has “not contravened any rules, laws or regulations”.

Northampton are likely to be investigated by Premiership Rugby – and they could be hit with a five-figure fine – by allowing North to be available for international rugby this weekend. The Australia game falls outside the International Rugby Board’s official autumn window, and Premiership Rugby’s policy is no non-England players should subsequently be released for matches or training camps.

That policy was agreed by all 12 Premiership clubs, with any breaches governed by a code of conduct.

In a statement, Northampton said: “The Saints management wants to make it clear that our agreement with George has not contravened any laws, rules or regulations. However, when it was finalised, the agreement included terms for his release to play international rugby which were outside Premiership Rugby board policy.”