Barcelona tied down captain Andres Iniesta for the rest of his career as the club announced on Friday the 33-year-old midfielder has agreed a "lifetime contract".

"Iniesta signed a lifetime contract with FC Barcelona on Friday, in a deal that will keep him at the club for the rest of his career," Barca said in a statement.

Along with five-time World Player of the Year Lionel Messi, Iniesta is Barca's most decorated player of all-time having won 30 trophies at club level, including eight La Liga titles and four Champions Leagues.

Iniesta has also made the second highest number of appearances in a Barca shirt behind Xavi Hernandez with 639 since his debut 15 years ago.

Born in the central Spanish region of Castilla-La Mancha before joining Barca at the age of 12, Iniesta is a beloved figure across Spain as he scored the winning goal in the 2010 World Cup final.

Normally determined to shy away from the spotlight, Iniesta spoke out on Thursday to urge negotiation and prevent a spiralling political crisis over the battle for Catalan independence deepening.

Hundreds required medical attention on Sunday as voters in a referendum on independence, deemed illegal by Spain's central government, clashed with police.

"I have never before publicly commented on situations that are so complex and involve such diverse emotions, but this situation we are experiencing is exceptional," Iniesta wrote in a Facebook post.

"One thing I know for sure: before we do any more harm, those who are responsible for all this must hold dialogue.

"Do it for all of us. We deserve to live in peace."

- Deal ends doubts -

Iniesta has previously tended to do his talking on the field as a fundamental figure in Barca's most successful ever era.

Alongside long-time midfield partner Xavi for both club and country, Iniesta formed the axis of Pep Guardiola's legendary side that won 14 trophies in four years between 2008 and 2012.

His previous contract was due to expire at the end of the season and doubts over his future were raised when he refuted Barca president Josep Maria Bartomeu's claims a deal "in principle" was in place last month.

Bartomeu has received fierce criticism for his handling of both sporting and institutional matters in recent months.

He decided to play Barca's home game against Las Palmas on Sunday behind closed doors as a protest against events in Catalonia on Sunday, leading to the resignation of two board members.

And Barca's haphazard approach in the transfer market following Neymar's world record 222 million euro departure to Paris Saint-Germain also saw Bartomeu face a vote of no confidence from disgruntled club members.

However, in tying down Iniesta, Bartomeu has at least ensured that one of Barca's all-time greats will see out the rest of his career at the Camp Nou.