De Jong believes he could have a key role to play.
The Holland international said: "Everybody is keen. He is still a player for Manchester City, we never doubted that.
"Of course he had some difficulties with the club but he is here now and we like to look to the future instead of the past.
"Nobody ever doubted his qualities. It was just the fact of him having some difficulties with the club.
"In the group, and as a player, he never changed. I think the qualities he had are an asset for any team, and also us at this stage."