The German international is tied to the Gelsenkirchen outfit with a contract running till 2010, and the Schalke board are still trying to convince him to pen an extension.
"I will only decide in the summer whether to extend my stay at Schalke or not," Kuranyi was quoted as saying by Bild.
"This is not the right moment to make a decision about my future. We have an important UEFA Cup game against Manchester City on Thursday.
"After the end of the season, I will have more time to think more carefully."
The Brazilian-born player, who already has 52 Germany caps and 19 goals under his belt, has recently fallen out of favor with national coach Joachim Loew.
Kuranyi abandoned a Germany training camp, after being excluded from the World Cup qualifier against Russia in October.
The incident put the player under fire from the Schalke fans, which fuelled talks that the former Stuttgart man might be out of the club by the end of the season.