Manchester City will reportedly be asked to pay £3.5million just to sign Mexican star Nery Castillo on a year's loan from Shakhtar Donetsk.
Castillo's agent has claimed the forward is on the verge of joining City but Shakhtar president Rinat Akhmetov insists a deal is a long way from completion.
Akhmetov outlined to the club's official website the terms which would allow the player's departure from the Ukrainian club.
"A one-year loan - five million euros and there will be no options, meaning a right to buy (Castillo)," said Akhmetov, the country's richest man.
"We will see in a year whether to bring him back to Shakhtar or if we sell him.
"The price could be 20, 30, 40 or 50 million euros."
And Akhmetov believes the £12.5m record buy, who can play in midfield or as a striker, needs to alter his mentality to prove he is worth his hefty transfer fee.
"He was a star at Olympiacos and he came here as a star," he added.
"He thought that because we paid 20 million euros for him his place was assured. He forgot that he had to win it."