Barcelona and Alexander Hleb have reached an agreement to terminate his contract by mutual consent.
The 30-year-old joined the Spanish and European champions in 2008 but has been used sparingly by coach Pep Guardiola.
Hleb has been loaned out to Stuttgart, Birmingham City and Wolfsburg during his tenure with the Catalans but has failed to win a permanent deal with these clubs.
However, the Belarus international is now free to look at other avenues as he looks to kick-start his career.
"Barcelona and the Belarusian player have reached an agreement for the early termination of the contract tying the player to the club, which would normally have ended on June 30th, 2012," a club statement said.
Olympiakos are now leading the chase for the services of the ex-Gunner and are long-term admirers of his talent.