Barcelona have agreed a deal with Arsenal to sign Thomas Vermaelen on a five-year contract.
The news that the 28-year-old Belgium defender is to make the switch was announced by both clubs on Saturday evening.
Arsenal confirmed Vermaelen passed his medical in Barcelona earlier that day, adding that his transfer is "subject to the completion of the normal regulatory process".
The fee is undisclosed for a player who had been club captain for the Barclays Premier League side for the past two seasons but was frequently on the bench last term, with Per Mertesacker and Laurent Koscielny the first-choice pairing at centre-back.
He made only 13 starts in all competitions and 21 appearances in total for Arsenal during the campaign, which concluded with him being an unused substitute in the Gunners' FA Cup final victory over Hull as they collected their first trophy in nine years.
Vermaelen was initially an integral part of the London club's defence after signing from Ajax in 2009, but form and fitness have subsequently put his starting spot in jeopardy.
He has played 150 times for Arsenal overall in five seasons, scoring 15 goals.
Vermaelen had been linked with Manchester United, but it is understood that Arsenal proposed a swap deal which the Red Devils were not prepared to do.
While indicating on Thursday that United were among the clubs to have made an offer for Vermaelen, Arsenal boss Arsene Wenger also said he would prefer any sale to be made to an overseas side.
Barcelona said Vermaelen will sign his contract on Sunday before having a photograph session with the media on the Nou Camp turf.
He will then be officially presented as the Catalan club's player at a press conference.