He signed a four-year-deal with the Swans in a likely swap deal for defender Ben Davies. The player was ecstatic about his decision.
The Iceland international had scored 7 goals in 18 games for the Swans back in 2012 before returning to London where he scored just 8 goals from 58 appearances.
He spoke after his unveiling and said: “It just feels right. The squad has changed a bit with new players, but the core is still here and I know a lot of the staff and of course the manager as I played with him while I was here last time.
“It’s not as if I’m joining a new team. I’m coming back after two years away.
“The club has really grown on and off the pitch. There’s a new training ground here for the first team and the academy.
“It was fantastic to see the club win the cup and go into the Europa League.
“The club has continued to progress and hopefully in the next few years we will get even bigger,” signed off the 24-year-old.