Vass, who will also cover fly-half, will begin training with the Saints squad in July. He has already made 26 appearances for Saints, following his Heineken Cup debut against Neath in 1999, and scored five tries.

He may well get the chance to further his experience in the Heineken Cup after Saints won qualification into next year’s competition with their late win against Bristol Rugby on Sunday.

Director of rugby Budge Pountney said: “When considering which scrum-halves we wanted to come into our squad, Ian’s name always cropped up. We are delighted that he is coming back home. It is a big decision on his behalf and will add great strength to our scrum-half department. We feel that his decision to come back will drive him to compete at the highest level.”

Vass said: “I am delighted to be coming back especially with the way Budge and Grase have been running the team and the way the squad has been playing. It is an opportunity to play the kind of rugby I like to play.”

He added: “I saw the result on Sunday and the fact we are in the Heineken Cup makes it even more exciting to be back playing for my home club at the highest club level.”