Tottenham are in talks with Shakhtar Donetsk over a fee for Manor Solomon.
Solomon joined Tottenham in a permanent transfer from Shakhtar last summer.
No transfer fee was required, due to FIFA regulations for players belonging to Russian and Ukrainian clubs.
Now, however, Shakhtar Donetsk CEO Sergiy Palkin says the parties are negotiating a compensation.
"We have had talks with Tottenham," he told ESPN. "I hope and believe that we will find a solution.
"We are now in, let's say, a negotiation process with them. I hope and believe that we will find a solution. Right now it is difficult to say anything specific because we are on the way in the negotiations."
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