The Frenchman, who was banned for five matches by an independent regulatory commission last month after being charged by the Football Association for performing a controversial 'quenelle' gesture to celebrate a goal at West Ham in December, confirmed the news on his Twitter account.
"Following discussions between the club and me, proposals have been made to me that I rejoined the group under certain conditions I cannot accept," he wrote. "Wishing to keep my integrity... I decided to free myself and to terminate the contract binding me with West Bromwich Albion until 2014, and now.
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