The 28 year old winger has played 206 games in the NRL – 147 with the Manly Sea Eagles and 59 with the Canberra Raiders. He has scored 83 tries and been of the most consistent players to ever wear the maroon and white.
Robertson joined Manly in 2006 after making his debut in the NRL with Canberra in 2001.
The specialist left winger said he will satisfy a life long ambition to have a season in the English Super League.
“A lot of my mates have done it and loved the experience so when the opportunity to give it a shot came up I grabbed it. I want to go over there whilst I’m enjoying my football and hopefully with another premiership under my belt. It will be difficult to leave Manly where I have loved my time and made lot of friends – especially my team mates,” Robertson said.
Coach Des Hasler said Robertson had been a mighty clubman for the Sea Eagles.
“We wish him well but he has a vital role to play for Manly in the weeks ahead in the final series. These are the games when he is at his best,” Hasler said.