Kevin De Bruyne's agent has dismissed Wolfsburg's claims that the Manchester City target is certain to stay with the Bundesliga runners-up.
Wolfsburg sporting director Klaus Allofs had insisted that the in-demand Belgium international would remain with the DFB-Pokal winners as he talked about giving the 24-year-old midfielder, who is under contract until 2019, a much-improved deal.
But De Bruyne's representative Patrick De Koster says he is yet to receive that offer and told Wolfsburg they would have to give his client a major pay rise to secure his future.
"Will Kevin definitely stay with Wolfsburg? I await their proposal," De Koster told reporters. "I have not sat down at the table with the club."
De Bruyne scored 16 goals and recorded 29 assists for Wolfsburg last season, attracting City's attention and becoming a reported target for Bayern Munich and Paris Saint-Germain.
And De Koster refused to guarantee that the playmaker will stay put, adding: "That remains to be seen. Who knows if Wolfsburg will make Kevin an offer that puts him in the top three earners in the league?
"In that case, let the club prove that he is incredibly important and that they themselves are ambitious. But they can call if they have a top offer prepared -- it could turn out to be a ridiculous proposal."
City are intent on bolstering their midfield this summer and have had two bids for Liverpool winger Raheem Sterling rejected, while Juventus' France international Paul Pogba is also on their radar.
De Bruyne is intent on challenging Bayern Munich for the title, telling Sport Bild: "Of course I hope to become champion with Wolfsburg. If you look at the development in the last years, we are on the right path."
But Wolfsburg coach Dieter Hecking has warned against rising expectations, saying: "It is a big challenge for us to repeat last season's success. It won't be achieved by talking alone."
Allofs also says that De Bruyne has room for improvement, adding: "I know no player that is at the end of his development at 24. We have to work on the details now.
"For example, [we must] make the coordination with his teammates even better. Kevin has improved his defensive game a lot, but there is some fine tuning to do."
ESPN FC correspondent Jens Weber contributed to this report.