Dimitri Seluk said talks have been under way for six months over an extension to Toure's current deal, which runs to 2015.
However, Seluk also suggested that things have not gone according to plan and he does not feel that Toure will stay.
Toure, who joined City from Barcelona for £24m in July 2010, is currently on international duty with the Ivory Coast but he said ahead of last month's Premier League game against Chelsea that he wanted to stay with the club for good.
"Of course, I'd love to stay at City. I'm here with the guys who love you, the guys who care about you.
"It's strange because throughout my career I have only been at clubs for two or three years, often changing after just one or two years. Here it's different. I want to stay longer."