A statement published on fcbarcelona.es confirmed the agreement between the clubs, although the former Galatasaray player will not be able to play an official game for Barcelona until January 2016 due to a transfer ban imposed by FIFA for breaching rules over the signings of under-age players.

That ban has not stopped Barca, who won the Primera Division, Copa del Rey and Champions League last season, from recruiting Spanish winger Aleix Vidal on a permanent transfer from Sevilla last month.

Arda's arrival will strengthen Barca's midfield following the departure of veteran captain Xavi, who has joined Qatari club Al Sadd after 24 years with the Catalan giants.

Arda may not have quite as much experience of the Primera Division, but he was certainly a successful signing at the Vicente Calderon.

He joined Atletico from Gala in 2011 and went on to make 127 appearances for the Rojiblancos, winning the Europa League in his first season before clinching the Copa del Rey in 2012-13.

The following season saw Arda score three goals and set up four more in 30 league appearances as Atletico won their first Spanish league title in 18 years.

He started 28 league games as Atletico finished third in 2014-15 to qualify for next season's Champions League.