That's according to Istanbul Basaksehir coach Abdullah Avci.
"The transfer of Arda will be announced on Thursday or Friday," he said.
"It hasn't been an easy transfer, Arda has been our goal for many years and I have to thank the president for this signing."
Although Barcelona have yet to announce anything or confirm the news, the player's agent also acknowledged that the deal had been completed.
"Arda has reached an agreement with Basaksehir and he doesn't want to listen to any other offers," Ahmet Bulut told Sporx. "He wants to go back to Istanbul."