Nalis will be fondly remembered for his spectacular strikes in a City shirt, none more so than his infamous volley against Leeds in September 2003.
Sheffield United manager Neil Warnock:
"I am delighted to announce that after extensive talks Lilian has agreed to join us for next season.
"He is the type of midfielder I have been looking to sign since Stuart McCall stopped playing - the right age, the right temperament and I think he'll make us a better team."
Lilian Nalis:
"There are lots of good youngsters here, I know them and the manager has told me about them. I want to be the concrete that holds them together.
"A manager will always want a more experienced player to help in difficult games or at difficult moments. I have the experience, ten years in France and then in Italy with Chievo Verona, so I enjoy a challenge. I know my job here and am not afraid of responsibility."
"I have played in the Premiership but it is also important that I know I can play at this level as well. I have proved that to people and myself.