Reports have surfaced Down Under that Tomkins is homesick, and is considering a return to the UK at the end of the season.
Despite Koukash not wanting to see Tomkins go to the other code, he has ruled out signing the full-back for his own team.
“Sam Tomkins is no longer a priority signing for me,” Koukash wrote in his Manchester Evening News column.
“If reports of Sam allegedly being homesick and ready to leave the New Zealand Warriors at the end of the season are to be believed, then I sincerely hope he stays in rugby league.
“I would be wanting him to come back to Wigan.
“I would hate to see a world class player of Sam’s stature ending up in rugby union.
“This must not happen and must be prevented.
“After losing Sam Burgess, it would be another devastating blow for our game to lose Tomkins too.
“We still do not really know what is happening but if Sam is to become available, I would be very happy to see him go back to Wigan.
“Sam is a good friend of mine. I loved to watch him play at Wigan.
“I was very keen to sign Sam when I first arrived at Salford and did everything in my power to get him.
“I will be watching developments with interest but that is as far as it goes this time.”
“We are now well covered in the full back role.
This is what I mean about Sam no longer falling under the priority signing bracket.”