“City are delighted to announce the signing of Brazilian midfielder Fernando,” read a statement on the club’s official website.
“The 26-year-old will join the Club from Porto and will wear the number six shirt next season.”
Details of Fernando’s contract have not yet been disclosed, yet it is believed a fee in the region of £12million (R216 million) was agreed.
The defensive midfielder, who came through the ranks at Brazilian club Vila Nova, joined Porto in 2007, winning four League titles, two Portuguese Cups as well as the UEFA Europa League.
And the 26-year-old expressed his delight at finalising his move to the Etihad.
“I am so happy to finally be joining Manchester City,” he told his new club’s official website.
“I’m looking forward to meeting my new team-mates and helping City to defend the title.
“It is a very exciting time to be part of this football club and I cannot wait to play in the Premier League.”
Meanwhile, City’s cross-town rivals Manchester United had bid for Spanish midfielder Ander Herrera rejected by his La Liga club Athletic Bilbao.
“The Athletic Club wishes to report that this week it rejected an offer from Manchester United FC, estimated at €36m, to transfer the federation and economic rights of the player Ander Herrera,” read a statement released by the club.
The 24-year-old was a target for United under David Moyes last season, yet it is believed his club are holding onto their talent until next month to exercise a clause in his contract which will see his release fee increase by £4.8million (R86 million).