Goalkeeper Joey Didulica has called on AZ Alkmaar to honour their promise and let him leave the Eredivisie champions this summer.
The Australian stopper is hoping to secure a move to Feyenoord, although the Rotterdam club are currently struggling to come up with the necessary funds.
Didulica told De Telegraaf: "Mister (Dirk) Scheringa has made me a promise, AZ would co-operate this summer in a transfer.
"I know that Feyenoord wants to get me and I want to join them very much. The deal with AZ is not on paper, it's a gentlemen's agreement.
"In the past winter there were possibilities for me, but then the club didn't want to let me go. I had understanding for that. Now they need to have understanding for me."