Te'o, who has played with the West Tigers and the Brisbane Broncos in the past and was selected in this year's State of Origin three game series with Queensland, will mark a significant career milestone this Thursday when he lines out for his 150th National Rugby League (NRL) appearance against the Brisbane Broncos.

Born in New Zealand, he made his senior international debut with Samoa in the 2008 Rugby League World Cup against France scoring two tries.

He will join Leinster Rugby once his season with the Rabbitohs concludes.

"This is a great step for me personally and is just the type of challenge that I was looking for at this stage in my career,"Te'o said.

"Leinster is one of the leading lights of Northern Hemisphere rugby and the opportunity to return to union was also an opportunity too good to pass."

Leinster Coach Matt O'Connor welcomed the signing and looked forward to his arrival.

"Ben is someone that we have taken an active interest in for some time now in particular as he made his intentions to change codes some time ago," O'Connor said.

"I was home during the summer and met with him a number of times. He is keen and eager to make a lasting impression at Leinster and to develop into a world class rugby player.

"He is a dynamic and explosive ball carrier and that physicality will enhance our offering both in attack and in our defence."