The permanent deal, which is subject to global clearance, brings an end to Nasri's six-year stay at the Etihad Stadium.
Nasri is set to earn around €4m per season, excluding bonuses, and leaves Manchester having won two Premier League titles - in 2012 and 2014, as well as League Cups in 2014 and 2016.
French midfielder Samir Nasri has joined Antalyaspor from Manchester City, the British football giants confirmed on Monday.
Thanks for the memories and good luck in Turkey, Samir!
Nasri spent last season on loan to Sevilla but he was part of the first-team group during pre-season and impressed Pep Guardiola with his application in training despite reports his team-mates were bemused by his presence on tour. In Turkey Nasri will play with some big names like former Tottenham Hotspur midfielder Sandro, former PSG striker Jérémy Ménez, former Arsenal defender Johan Djourou, as well as club captain Samuel Eto'o.
Brighton have reached an agreement to sign Ghana striker Raphael Dwamena from Swiss club FC Zurich.
A statement read: "Brighton & Hove Albion can confirm that the club has reached agreement with FC Zurich for the permanent transfer of Ghanaian global, Raphael Dwamena, subject to work permit and worldwide clearance".
"The 21-year-old striker has also agreed personal terms with the club and is now awaiting clearance to travel to the United Kingdom for his medical".