Manchester City have made an "astonishing" wage offer to winger Kevin de Bruyne, claims Wolfsburg's director of sport Klaus Allofs.
De Bruyne, 24, has been left out of Friday's game with Schalke as talks continue over a move to City.
"We had to take it seriously. Finally we decided to start negotiations with City," added Allofs.
"But the deal is not already done. So hopefully we will find an end on Thursday night or Friday morning."
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City have not responded to reports a £58m deal has been agreed for the Belgium international.
"During Thursday, we have gone on with negotiations and we've got closer to each other," added Allofs.
"He's had an astonishing, astonishing offer from City and we can't compete with that.
"I would prefer to keep him, not to get the money.
"But the money now is really the issue because Kevin was qualified with Wolfsburg for the Champions League and he was a key player and took the next step."
Former Chelsea midfielder De Bruyne, 24, joined Wolfsburg in January 2014.
Last season, the Belgium international scored 10 goals and provided 21 assists in the Bundesliga.
"At Chelsea, he was not that good and I know the story because I took him to Werder Bremen two years before and then to Wolfsburg," said Allofs.
"It will be very difficult - apart from Bayern Munich - to compete with the Premier League in the future."