Gatland names his squad for the tour of Australia later today, with Wilkinson expected to miss out on a place despite his impressive recent form.
He told the Daily Mail: "Ask any Australian who they don't want to see walk off that plane and Jonny Wilkinson will be top of the list.
"Forget the fact he is an English icon who won the World Cup; he should make the squad on merit. It comes down to whether, at 33, Wilkinson is capable of dictating play with a running game and of course he can. People focus on Wilkinson's kicking because he is the best kicker in the world, but his passing game is second to none and he was a key player in setting the tempo for my England team, freeing up our strike runners like Jason Robinson.
"He is playing behind a strong pack at Toulon and has seen off two England fly-halves, Leicester's Toby Flood and Saracens' Owen Farrell, in the Heineken Cup. He is in amazing shape and mentally he will be one of the toughest players in the squad."
Wilkinson will find out if he has made the cut this morning when Gatland reveals his squad at around 11am.