Fenerbahce claim Al-Ittihad are to blame for the collapse of their deal to sign France midfielder N’Golo Kante.
The Turkish club said, external they had fulfilled their part of the transfer and, in a deal that involved Morocco striker Youssef En-Nesyri moving in the opposite direction, agreements had “been reached with the players”.
Fenerbahce added that “the medical examinations of the player” had been completed and they had met their “obligations completely and on time”.
“However, due to the opposing club’s incorrect entry of the relevant Transfer Matching System information, the transactions could not be completed within the transfer registration period, independently of our club,” they continued.
Fenerbahce said they asked for an extension to complete the deal and held talks with Fifa as “all steps were taken to resolve the issue”.
“Despite this, the opposing club has not completed the transactions without providing any justification to us,” added Fenerbahce.
“As a result of these developments, the transfer process unfortunately could not be finalised.”
BBC Sport has asked Al-Ittihad for a response.